Jones Lang LaSalle (JLL) 10-Q 2 Nov 20 2020 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2020	Oct. 27, 2020
Document and Entity Information [Abstract]
Entity Registrant Name	Jones Lang LaSalle Incorporated
Entity Central Index Key	0001037976
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		51,302,899
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q3
Document Type	10-Q
Amendment Flag	false
Entity Incorporation, State or Country Code	MD
Document Period End Date	Sep. 30, 2020
Entity Shell Company	false
Entity Current Reporting Status	Yes

Cover Document

Cover Document	9 Months Ended
	Sep. 30, 2020
Document Information [Line Items]
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Title of 12(b) Security	Common Stock, par value $0.01
Entity File Number	1-13145
Entity Registrant Name	Jones Lang LaSalle Incorporated
Document Type	10-Q
Entity Incorporation, State or Country Code	MD
Entity Tax Identification Number	36-4150422
Entity Address, Address Line One	200 East Randolph Drive
Entity Address, City or Town	Chicago,
Entity Address, State or Province	IL
Entity Address, Postal Zip Code	60601
City Area Code	(312)
Local Phone Number	782-5800
Trading Symbol	JLL
Security Exchange Name	NYSE
Entity Shell Company	true
Document Period End Date	Sep. 30, 2020
Document Transition Report	false
Entity Shell Company	false
Entity Emerging Growth Company	false

Consolidated Balance Sheets (un

Consolidated Balance Sheets (unaudited) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 440	$ 451.9
Trade receivables, net of allowances	1,439.9	2,034.3
Notes and other receivables	443.1	472.8
Accounts Receivable, Reimbursed by Client, Current	1,357.1	1,671.2
Loans Receivable, Gross, Mortgage Warehouse Lending.	1,750.6	527.1
Contract with Customer, Asset, after Allowance for Credit Loss, Current	293	333.4
Prepaid Expense and Other Assets, Current	444.8	377.9
Total current assets	6,168.5	5,868.6
Property and equipment, net of accumulated depreciation	675.4	701.9
Operating Lease, Right-of-Use Asset	756.8	804.4
Goodwill	4,164	4,168.2
Identified intangibles, net of accumulated amortization	653.9	682.6
Investments in real estate ventures	389.6	404.2
Long-term receivables	239.8	250.2
Deferred Income Tax Assets, Net	235.3	245.4
Deferred Compensation Plan Assets	410.7	349.9
Other	208.1	197.2
Total assets	13,902.1	13,672.6
Current liabilities:
Accounts Payable and Accrued Liabilities, Current	1,096.7	1,289.4
Accounts Payable, Reimbursed by Client, Current	1,030.3	1,245.8
Accrued compensation & benefits	1,113.7	1,729.2
Short-term Debt	106.4	120.1
Short-term contract liabilities and deferred income	161	158.8
Business Combination, Contingent Consideration, Liability, Current	92.6	74.4
Warehouse facilities	1,723.8	515.9
Operating Lease, Liability, Current	164	153.4
Other	313.6	203.2
Total current liabilities	5,802.1	5,490.2
Noncurrent liabilities:
Long-term Line of Credit, Noncurrent, Net of Debt Issuance Costs	390.4	512.7
Long-term debt, net of debt issuance costs	682.9	664.6
Deferred Tax Liabilities, Net	42.9	106
Deferred compensation	405.9	374.3
Business Combination, Contingent Consideration, Liability, Noncurrent	39.6	124.1
Operating Lease, Liability, Noncurrent	705.1	751.2
Other	539.1	436.2
Total liabilities	8,608	8,459.3
Redeemable Noncontrolling Interest	7.9	8.6
Company shareholders' equity:
Common stock, $.01 par value per share	0.5	0.5
Additional paid-in capital	2,008.1	1,962.8
Retained earnings	3,725.9	3,588.3
Treasury Stock, Value	(47.8)	0
Shares held in trust	(5.6)	(5.7)
Accumulated Other Comprehensive Income (Loss), Net of Tax	(477.4)	(427.8)
Total Company shareholders' equity	5,203.7	5,118.1
Noncontrolling interest	82.5	86.6
Total equity	5,286.2	5,204.7
Total liabilities and equity	$ 13,902.1	$ 13,672.6

Consolidated Balance Sheets (_2

Consolidated Balance Sheets (unaudited) (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Assets
Trade receivables, allowances	$ 81.3	$ 68.1
Contract with Customer, Asset, Allowance for Credit Loss, Current	2.8
Property and equipment, accumulated depreciation	775.9	660.7
Identified intangibles, with finite useful lives, accumulated amortization	277	214.8
Investments, Fair Value Disclosure	$ 299	$ 328.6
Company shareholders' equity
Treasury Stock, Common, Shares	429,617
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	100,000,000	100,000,000
Common Stock, Shares, Issued	51,968,753	51,549,654
Common Stock, Shares, Outstanding	51,539,136	51,549,654
Long-Term Senior Notes [Member]
Line of Credit Facility [Line Items]
Unamortized Debt Issuance Expense	$ 2.7	$ 3.1
Line of Credit [Member]
Line of Credit Facility [Line Items]
Unamortized Debt Issuance Expense	$ 9.6	$ 12.3

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income (unaudited) - USD ($) shares in Thousands, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Income Statement [Abstract]
Revenue Before Reimbursements	$ 2,091.4	$ 2,545.8	$ 6,152.9	$ 6,855.6
Reimbursement Revenues	1,886.7	1,949.8	5,591.6	5,727.1
Revenue	3,978.1	4,495.6	11,744.5	12,582.7
Operating expenses:
Compensation and benefits	1,198.7	1,488.6	3,698.5	4,007.2
Operating, administrative and other	649.4	762	1,981.5	2,241.4
Cost of Reimbursable Expenses	1,886.7	1,949.8	5,591.6	5,727.1
Depreciation and amortization	54.9	53.6	166.8	145.6
Restructuring and acquisition charges	33.5	70	75.8	114.3
Total operating expenses	3,823.2	4,324	11,514.2	12,235.6
Operating Income (Loss)	154.9	171.6	230.3	347.1
Interest Expense, Net of Interest Income	12.3	18	41.8	41.2
Equity earnings from real estate ventures	15	17.1	1.4	32.3
Other Nonoperating Income (Expense)	2.7	0.7	8.8	1.2
Income before income taxes and noncontrolling interest	160.3	171.4	198.7	339.4
Provision for income taxes	25.7	42.1	32.2	77.6
Net income	134.6	129.3	166.5	261.8
Net income attributable to noncontrolling interest	2.7	0.4	14.1	0.9
Net income attributable to the Company	131.9	128.9	152.4	260.9
Dividend, Share-based Payment Arrangement	0	0	0	0.2
Net income attributable to common shareholders	$ 131.9	$ 128.9	$ 152.4	$ 260.7
Basic earnings per common share (in dollars per share)	$ 2.55	$ 2.50	$ 2.95	$ 5.47
Basic weighted average shares outstanding (in shares)	51,761	51,528	51,670	47,672
Diluted earnings per common share (in dollars per share)	$ 2.52	$ 2.47	$ 2.92	$ 5.42
Diluted weighted average shares outstanding (in shares)	52,247	52,104	52,224	48,077
Common Stock, Dividends, Per Share, Declared	$ 0	$ 0	$ 0	$ 0.43
Other comprehensive income:
Net income attributable to the Company	$ 131.9	$ 128.9	$ 152.4	$ 260.9
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax and Reclassification Adjustment, Attributable to Parent	0.7	0.1	0.7	(1.7)
Foreign currency translation adjustments	59.3	(34.6)	(50.3)	(26.6)
Comprehensive income attributable to the Company	$ 191.9	$ 94.4	$ 102.8	$ 232.6

Consolidated Statement of Chang

Consolidated Statement of Changes in Equity (unaudited) - USD ($) $ in Millions	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Treasury Stock [Member]	Retained Earnings [Member]	Shares Held in Trust [Member]	AOCI Attributable to Parent [Member]	Noncontrolling Interest [Member]
Common Stock, Shares, Issued at Dec. 31, 2018	45,599,418
Balances at Dec. 31, 2018	$ 3,734.5	$ 0.5	$ 1,057.3		$ 3,095.7	$ (5.8)	$ (456.2)	$ 43
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (Loss), Including Portion Attributable to Nonredeemable Noncontrolling Interest	21.2				21.3			(0.1)
Shares issued under stock compensation programs (in shares)		198,575
Shares issued under stock compensation programs	(2)		(2)
Shares repurchased for payment of taxes on stock awards (in shares)		(58,750)
Shares repurchased for payment of taxes on stock awards	(9.7)		(9.7)
Amortization of stock compensation	7		7
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax and Reclassification Adjustment, Attributable to Parent							(1)
Foreign currency translation adjustments	31.3
Distributions to noncontrolling interest	9.8							9.8
Balances at Mar. 31, 2019	$ 3,795.1	$ 0.5	1,056.6		3,117	(5.8)	(425.9)	52.7
Common Stock, Shares, Issued at Dec. 31, 2018	45,599,418
Balances at Dec. 31, 2018	$ 3,734.5	0.5	1,057.3		3,095.7	(5.8)	(456.2)	43
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax							(1.7)
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax and Reclassification Adjustment, Attributable to Parent	(1.7)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax							(26.6)
Foreign currency translation adjustments	$ (26.6)
Common Stock, Shares, Issued at Sep. 30, 2019	51,534,119
Balances at Sep. 30, 2019	$ 4,858.1	0.5	1,937.3		3,336.7	(5.7)	(484.5)	73.8
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Stock, Shares, Outstanding	45,739,243
Net Income (Loss) Attributable to Redeemable Noncontrolling Interest	$ 0.1
Balances at Mar. 31, 2019	3,795.1	$ 0.5	1,056.6		3,117	(5.8)	(425.9)	52.7
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (Loss), Including Portion Attributable to Nonredeemable Noncontrolling Interest	111.2				110.7			0.5
Shares issued under stock compensation programs (in shares)		31,820
Shares issued under stock compensation programs	(0.8)		(0.8)
Shares repurchased for payment of taxes on stock awards (in shares)		(8,375)
Shares repurchased for payment of taxes on stock awards	(0.7)		(0.7)
Amortization of stock compensation	12.9		12.9
Dividends, Common Stock, Cash	(19.9)				(19.9)
(Increase) Decrease In Common Stock Held In Trust	(0.1)					(0.1)
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, Tax, Attributable to Parent	(0.8)
Foreign currency translation adjustments	(23.3)
Distributions to noncontrolling interest	$ 0.1							0.1
Common Stock, Shares, Issued at Jun. 30, 2019	45,762,688
Balances at Jun. 30, 2019	$ 3,875.3	$ 0.5	1,069.6		3,207.8	(5.9)	(450)	53.3
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (Loss), Including Portion Attributable to Nonredeemable Noncontrolling Interest	129.3				128.9			0.4
Shares issued under stock compensation programs (in shares)		49,292
Shares issued under stock compensation programs	(0.9)		(0.9)
Stock Issued During Period, Shares, Acquisitions		5,733,603
Stock Issued During Period, Value, Acquisitions	841.2		841.2
Shares repurchased for payment of taxes on stock awards (in shares)		(11,464)
Shares repurchased for payment of taxes on stock awards	(2.1)		(2.1)
Amortization of stock compensation	27.7		27.7
(Increase) Decrease In Common Stock Held In Trust	0.2					0.2
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax							(0.1)
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax and Reclassification Adjustment, Attributable to Parent	0.1						0.1
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax							(34.6)
Foreign currency translation adjustments	(34.6)
Distributions to noncontrolling interest	$ 20.1							20.1
Common Stock, Shares, Issued at Sep. 30, 2019	51,534,119
Balances at Sep. 30, 2019	$ 4,858.1	$ 0.5	1,937.3		3,336.7	(5.7)	(484.5)	73.8
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Treasury Stock, Value	$ 0			$ 0
Common Stock, Shares, Outstanding	51,549,654
Common Stock, Shares, Issued at Dec. 31, 2019	51,549,654
Balances at Dec. 31, 2019	$ 5,204.7	$ 0.5	1,962.8		3,588.3	(5.7)	(427.8)	86.6
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (Loss), Including Portion Attributable to Nonredeemable Noncontrolling Interest	17.6				5.3			12.3
Shares issued under stock compensation programs (in shares)		363,308
Shares issued under stock compensation programs	(4.4)		(4.4)
Shares repurchased for payment of taxes on stock awards (in shares)		(102,370)
Shares repurchased for payment of taxes on stock awards	(16.2)		(16.2)
Amortization of stock compensation	18.6		18.6
Stock Repurchased During Period, Shares				(187,753)
Treasury Stock, Value, Acquired, Cost Method				$ (25)
(Increase) Decrease In Common Stock Held In Trust	0.1
Cumulative Effect on Retained Earnings, Net of Tax. | Accounting Standards Update 2016-13 [Member]					(14.9)
Foreign currency translation adjustments	(143.4)
Distributions to noncontrolling interest	(17)							(17)
Balances at Mar. 31, 2020	$ 5,028.9	$ 0.5	1,969.6		3,578.7	(5.6)	(571.2)	81.9
Common Stock, Shares, Issued at Dec. 31, 2019	51,549,654
Balances at Dec. 31, 2019	$ 5,204.7	0.5	1,962.8		3,588.3	(5.7)	(427.8)	86.6
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax							(0.7)
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax and Reclassification Adjustment, Attributable to Parent	0.7
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax							(50.3)
Foreign currency translation adjustments	$ (50.3)
Common Stock, Shares, Issued at Sep. 30, 2020	51,968,753
Balances at Sep. 30, 2020	$ 5,286.2	0.5	2,008.1		3,725.9	(5.6)	(477.4)	82.5
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Treasury Stock, Value				(25)
Common Stock, Shares, Outstanding	51,622,839
Balances at Mar. 31, 2020	$ 5,028.9	$ 0.5	1,969.6		3,578.7	(5.6)	(571.2)	81.9
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (Loss), Including Portion Attributable to Nonredeemable Noncontrolling Interest	14.2				15.2			(1)
Shares issued under stock compensation programs (in shares)		23,762
Shares issued under stock compensation programs	(0.6)			(0.6)
Shares repurchased for payment of taxes on stock awards (in shares)		(4,546)
Shares repurchased for payment of taxes on stock awards	(1)		(1)
Amortization of stock compensation	30.7		30.7
(Increase) Decrease In Common Stock Held In Trust	(0.1)					(0.1)
Foreign currency translation adjustments	33.8
Distributions to noncontrolling interest	2.3							2.3
Balances at Jun. 30, 2020	$ 5,109.4	$ 0.5	1,999.3		3,593.9	(5.7)	(537.4)	83.2
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Treasury Stock, Value				(24.4)
Common Stock, Shares, Outstanding	51,642,055
Net Income (Loss) Attributable to Redeemable Noncontrolling Interest	$ (0.2)
Net Income (Loss), Including Portion Attributable to Nonredeemable Noncontrolling Interest	134.8				131.9			2.9
Shares issued under stock compensation programs (in shares)		221,527
Shares issued under stock compensation programs	(0.5)		(1.2)	$ (1.6)	(0.1)
Shares repurchased for payment of taxes on stock awards (in shares)		(66,315)
Shares repurchased for payment of taxes on stock awards	(6.3)		(6.3)
Amortization of stock compensation	16.3		16.3
Stock Repurchased During Period, Shares				(258,131)
Treasury Stock, Value, Acquired, Cost Method	(25)			$ (25)
(Increase) Decrease In Common Stock Held In Trust	0.1					0.1
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax							0.7
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax and Reclassification Adjustment, Attributable to Parent	0.7						0.7
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax							59.3
Foreign currency translation adjustments	59.3
Distributions to noncontrolling interest	$ (3.6)							(3.6)
Common Stock, Shares, Issued at Sep. 30, 2020	51,968,753
Balances at Sep. 30, 2020	$ 5,286.2	$ 0.5	$ 2,008.1		$ 3,725.9	$ (5.6)	$ (477.4)	$ 82.5
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Treasury Stock, Value	$ (47.8)			$ (47.8)
Common Stock, Shares, Outstanding	51,539,136

Consolidated Statement of Cha_2

Consolidated Statement of Changes in Equity Consolidated Statement of Changes in Equity (Parenthetical) - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Consolidated Statement of Change in Equity (Parenthetical) [Abstract]
Common Stock, Dividends, Per Share, Declared	$ 0	$ 0	$ 0	$ 0.43

Consolidated Statements of Cash

Consolidated Statements of Cash Flows (unaudited) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Cash flows used for operating activities:
Net income	$ 166.5	$ 261.8
Adjustments to reconcile net income to net cash used in operating activities:
Distributions of earnings from real estate ventures	10.4	12
Other adjustment, net	238.8	169.2
Changes in working capital, net	(52.6)	(694.5)
Net cash used in operating activities	363.1	(251.5)
Cash flows used in investing activities:
Net capital additions - property and equipment	(112.5)	(131.1)
Net investment activity (less than wholly-owned)	(10.2)	(67.6)
Business acquisitions, net of cash acquired	0	(789.2)
Payments to Acquire Interest in Joint Venture	(63.2)	(65.6)
Proceeds from Real Estate and Real Estate Joint Ventures	30.5	24.4
Other, net	31.2	35
Net cash used in investing activities	(124.2)	(994.1)
Cash flows provided by financing activities:
Proceeds from Long-term Lines of Credit	4,404	4,705
Repayments of Long-term Lines of Credit	(4,529)	(3,580)
Proceeds from (Repayments of) Short-term Debt	(17.1)	68.6
Payment for Contingent Consideration Liability, Financing Activities	(28.9)	(39.8)
Payments of Ordinary Dividends, Common Stock	0	(19.9)
Payments for Repurchase of Common Stock	(50)	0
Other, net	(22.8)	60.7
Net cash provided by financing activities	(243.8)	1,194.6
Effect of currency exchange rate on Cash and Cash Equivalents	(4.3)	(9.4)
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect	(9.2)	(60.4)
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	652.1	634.2
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	642.9	573.8
Supplemental disclosure of cash flow information:
Restricted Cash, beginning of period	200.2	153.3
Restricted Cash, end of period	202.9	171.6
Cash paid during the period for:
Interest Paid, Excluding Capitalized Interest, Operating Activities	35	36.7
Income taxes, net of refunds	101.6	218.8
Operating Lease, Payments	142	127.7
Non-cash activities
Business acquisitions, including contingent consideration	0	842.7
Deferred business acquisition obligations	$ 0	$ 6.5

Interim Information

Interim Information	9 Months Ended
	Sep. 30, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Interim Information	1. INTERIM INFORMATION Readers of this quarterly report should refer to the audited financial statements of Jones Lang LaSalle Incorporated ("JLL," which may also be referred to as "the Company" or as "we," "us" or "our") for the year ended December 31, 2019 , which are included in our 2019 Annual Report on Form 10-K, filed with the United States Securities and Exchange Commission ("SEC") and also available on our website ( www.us.jll.com ), since we have omitted from this quarterly report certain footnote disclosures which would substantially duplicate those contained in such audited financial statements. You should also refer to the "Summary of Critical Accounting Policies and Estimates" section within Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations and to Note 2, Summary of Significant Accounting Policies, in the Notes to Consolidated Financial Statements in our 2019 Annual Report on Form 10-K for further discussion of our significant accounting policies and estimates. Our Condensed Consolidated Financial Statements as of September 30, 2020 , and for the periods ended September 30, 2020 and 2019 , are unaudited. In the opinion of management, we have included all adjustments (consisting solely of normal recurring adjustments) necessary for a fair presentation of the Condensed Consolidated Financial Statements for these interim periods. Historically, our quarterly revenue and profits have tended to increase from quarter to quarter as the year progresses. This is the result of a general focus in the real estate industry on completing transactions by calendar year end, while certain expenses are recognized evenly throughout the year. Our LaSalle Investment Management ("LaSalle") segment generally earns investment-generated performance fees on clients' real estate investment returns when assets are sold, the timing of which is geared toward the benefit of our clients, as well as co-investment equity gains and losses, primarily dependent on underlying valuations. Within our Real Estate Services ("RES") segments, revenue from transaction-based activities (e.g. leasing and capital markets) is driven by the size and timing of our clients' transactions and can fluctuate significantly from period to period. The COVID-19 pandemic may have a material impact on the historical seasonality of our revenue and profits. A significant portion of our compensation and benefits expense is from incentive compensation plans, which we generally accrue throughout the year based on progress toward annual performance targets. This process can result in significant fluctuations in quarterly compensation and benefits expense from period to period. Non-variable operating expenses, which we recognize when incurred during the year, are relatively constant on a quarterly basis. We provide for the effects of income taxes on interim financial statements based on our estimate of the effective tax rate for the full year, which we base on forecasted income by country and expected enacted tax rates. As required, we adjust for the impact of discrete items in the quarters in which they occur. Changes in the geographic mix of income, including as a result of the COVID-19 pandemic, can impact our estimated effective tax rate. As a result of the items mentioned above, the results for the periods ended September 30 are not fully indicative of what our results will be for the full fiscal year.

New Accounting Standards New Ac

New Accounting Standards New Accounting Standards	9 Months Ended
	Sep. 30, 2020
Text Block [Abstract]
New Accounting Standards	2. NEW ACCOUNTING STANDARDS Recently adopted accounting guidance In June 2016, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") No. 2016-13, Financial Instruments - Credit Losses (ASC Topic 326) , which created a new framework to evaluate financial instruments, such as trade receivables, for expected credit losses. This new framework replaced the existing incurred loss approach and is expected to result in more timely recognition of credit losses. On January 1, 2020, we adopted ASU No. 2016-13 using a modified-retrospective approach, as required by the ASU. The adoption impacted our methodology of reserving for (i) Trade receivables, (ii) other receivable-related financial assets, specifically contract assets, and (iii) off-balance sheet credit exposures within the scope of this ASU. Specifically, we evaluated our historical reserve balances for Trade receivables and the related write-off activity and developed a forward-looking process for adoption. We also evaluated our loss-sharing guarantee obligation for certain mortgage loans we originate, sell and retain the servicing rights. The following sections discuss our updated reserve methodologies. Trade Receivables We estimate an allowance to provide for uncollectible accounts receivable, which is applied upon recognition of the receivable. We base this estimate on historical experience combined with a review of the receivable aging, current and expected economic conditions, and client credit quality. The estimate also includes specifically identified amounts for which payment has become unlikely. As trade receivables are due within one year, changes to economic conditions are not expected to have a significant impact on our estimate of expected credit losses. However, we will monitor economic conditions on a quarterly basis to determine if any adjustments are deemed necessary. Notes and Other Receivables and Long-Term Receivables We make ongoing assessments of the collectability of outstanding Notes and other receivables and Long-term receivables, considering both objective and subjective factors such as the aging profile of outstanding balances, the contractual terms of repayment, and credit quality. Aspects of credit quality considered in our assessments of collectability include historical experience, current and expected economic conditions, and our broader business relationship with the obligor. We record an allowance against the outstanding balance when our assessments determine payment has become unlikely. After all collection efforts have been exhausted by management, the outstanding balance is written off against the reserve. Historically, credit quality deterioration to the point of impairment or non-performance in our Notes and other receivables and Long-term receivables has been limited and has not had a material impact on the Condensed Consolidated Financial Statements. Reimbursable Receivables We record an allowance based on specific identification of an uncollectible reimbursable receivable, considering current and future economic conditions as well as client credit quality. Historically, we have not experienced any material collection issues and, as such, have not applied a formulaic reserve to these receivables. Contract Assets Contract assets include amounts recognized as revenue for which we are not yet entitled to payment for reasons other than the passage of time, but that do not constrain revenue recognition. Historically, we have not recognized a provision for contract assets. Under ASC Topic 326, we include Contract assets in our reserving process and assess the risk of loss similar to our methodology for Trade receivables, since Contract assets are reclassified to Trade receivables when we become entitled to payment. Accordingly, a reserve is applied upon recognition of the contract asset. Financial Guarantees Certain loans we originate and sell under the Fannie Mae Delegated Underwriting and Servicing (“DUS”) program retain a percentage of the risk of loss. This loss-sharing aspect of the program represents an off-balance sheet credit exposure, and we have established a contingent reserve ("loan loss guarantee reserve") for this risk in accordance with ASC Topic 326. To estimate the reserve, we use a model that analyzes historical losses, current and expected economic conditions, and reasonable and supportable forecasts. The model also considers specific details of the underlying property used as collateral, such as occupancy and financial performance. The loan loss guarantee reserve is calculated on an individual loan level. As of September 30, 2020, the loan loss guarantee reserve was $45.7 million and was included within Other liabilities on the Condensed Consolidated Balance Sheets. This balance reflected a notable increase from our opening balance (reflected in the table below) as a result of incorporating, into our model, economic conditions and projections related to the COVID-19 pandemic. The loss-sharing guarantee obligation (in accordance with ASC Topic 460, Guarantees ) represents the non-contingent obligation incurred as a result of issuing a loss-sharing guarantee as part of our participation in the DUS program and is separate from the loan loss guarantee reserve discussed above. See Note 10, Commitments and Contingencies , for further information on the DUS program and the loss-sharing guarantee obligation. The following table details the cumulative impact to retained earnings upon adoption of ASC Topic 326. Published Adjustment due to As Reported Under December 31, 2019 adoption of ASC Topic 326 on January 1, 2020 (in millions) (audited) ASC Topic 326 (unaudited) Assets Allowance for trade receivables $ (68.1 ) (3.6 ) $ (71.7 ) Deferred tax assets, net 245.4 5.5 250.9 Allowance for contract assets (1) — (1.7 ) (1.7 ) Liabilities and equity Loan loss guarantee reserve (2) $ — 15.1 $ 15.1 Retained earnings 3,588.3 (14.9 ) 3,573.4 1 The portion of the allowance for long-term contract assets is included within Other assets on the Condensed Consolidated Balance Sheets. 2 Included within Other liabilities on the Condensed Consolidated Balance Sheets

Revenue Recognition Revenue Rec

Revenue Recognition Revenue Recognition (Notes)	9 Months Ended
	Sep. 30, 2020
Revenue from Contract with Customer [Abstract]
Revenue from Contract with Customer [Text Block]	3. REVENUE RECOGNITION Revenue excluded from the scope of ASC Topic 606 - Our mortgage banking and servicing operations - such as Mortgage Servicing Rights ("MSR")-related activity, loan origination fees, and servicing income - are excluded from the scope of ASC Topic 606. Such revenue was included entirely within Americas Capital Markets and is presented below. Three Months Ended September 30, Nine months ended September 30, (in millions) 2020 2019 2020 2019 Revenue excluded from scope of ASC Topic 606 $ 72.0 74.3 $ 174.7 137.6 Contract assets and liabilities - Our contract assets, net of allowance, are included in Short-term contract assets and Other assets and our contract liabilities are included in Short-term contract liabilities and deferred income on our Condensed Consolidated Balance Sheets. The majority of contract liabilities are recognized as revenue within 90 days. Such contract assets and liabilities are presented below. (in millions) September 30, 2020 December 31, 2019 Contract assets, gross $ 389.8 419.3 Contract asset allowance (3.2 ) — Contract assets, net $ 386.6 419.3 Contract liabilities $ 85.7 87.7 Remaining performance obligations - Remaining performance obligations represent the aggregate transaction price for contracts where our performance obligations have not yet been satisfied. As of September 30, 2020 , the aggregate amount of transaction price allocated to remaining performance obligations represented less than 5% of our total revenue. In accordance with ASC Topic 606, excluded from the aforementioned remaining performance obligations are (i) amounts attributable to contracts expected to be completed within 12 months and (ii) variable consideration for services performed as a series of daily performance obligations, such as facilities management, property management, and LaSalle contracts. Contracts within these businesses represent a significant portion of our contracts with customers not expected to be completed within 12 months.

Business Segments

Business Segments	9 Months Ended
	Sep. 30, 2020
Segment Reporting [Abstract]
Business Segments	4. BUSINESS SEGMENTS We manage and report our operations as four business segments: The three geographic regions of RES including: (1) Americas, (2) Europe, Middle East and Africa ("EMEA"), and (3) Asia Pacific; and (4) LaSalle. Each geographic region offers our full range of real estate services, including agency leasing and tenant representation, capital markets, property and facility management, project and development management, energy management and sustainability, construction management, and advisory, consulting and valuation services. LaSalle provides investment management services on a global basis to institutional investors and high-net-worth individuals. We allocate all indirect expenses to our segments, other than interest and income taxes, as nearly all expenses incurred benefit one or more of the segments. Allocated expenses primarily consist of corporate global overhead, which we allocate to the business segments based on the budgeted operating expenses of each segment. Segment income does not include (i) restructuring and acquisition charges, (ii) interest expense, net of interest income, (iii) other income, and (iv) provision for income tax, which are otherwise included in Net income on the Consolidated Statements of Comprehensive Income. The Chief Operating Decision Maker of JLL measures and evaluates the segment results based on Segment income for purposes of making decisions about allocating resources and assessing performance. As of September 30, 2020 , we define the Chief Operating Decision Maker collectively as our Global Executive Board, which comprises the following: • Chief Executive Officer and President • Chief Executive Officers of each of our four business segments • Chief Financial Officer • Chief Executive Officer of Corporate Solutions • Chief Human Resources Officer • Chief Executive Officer of Capital Markets • Co-Chief Executive Officers of JLL Technologies Summarized financial information by business segment is as follows. Three Months Ended September 30, Nine Months Ended September 30, (in millions) 2020 2019 2020 2019 Americas Leasing $ 325.2 472.7 $ 1,022.2 1,354.3 Capital Markets 190.8 323.2 579.0 553.1 Property & Facility Management 1,433.3 1,386.3 4,331.6 4,119.2 Project & Development Services 336.2 406.0 917.9 1,091.5 Advisory, Consulting and Other 95.3 99.4 282.2 283.2 Revenue $ 2,380.8 2,687.6 $ 7,132.9 7,401.3 Depreciation and amortization $ 36.4 35.3 $ 112.9 88.9 Equity earnings $ 4.8 1.5 $ 20.4 1.6 Segment income $ 140.0 177.9 $ 277.1 359.1 EMEA Leasing $ 58.5 72.2 $ 153.3 190.3 Capital Markets 73.3 106.2 196.5 248.7 Property & Facility Management 348.7 387.1 1,044.2 1,137.0 Project & Development Services 190.8 234.2 558.3 633.9 Advisory, Consulting and Other 72.5 62.9 173.6 194.4 Revenue $ 743.8 862.6 $ 2,125.9 2,404.3 Depreciation and amortization $ 9.8 10.1 $ 28.0 32.7 Equity earnings (losses) $ 0.8 — $ 0.8 (1.0 ) Segment income (loss) $ (1.9 ) 13.8 $ (55.8 ) (17.9 ) Asia Pacific Leasing $ 46.6 59.4 $ 105.8 161.5 Capital Markets 20.4 50.6 66.1 128.2 Property & Facility Management 521.3 539.4 1,568.5 1,630.6 Project & Development Services 104.5 145.7 296.5 393.9 Advisory, Consulting and Other 50.4 38.7 133.7 123.5 Revenue $ 743.2 833.8 $ 2,170.6 2,437.7 Depreciation and amortization $ 6.9 6.5 $ 20.5 19.3 Equity earnings $ 0.9 0.7 $ 0.7 1.4 Segment income $ 35.8 31.5 $ 57.4 59.5 LaSalle Advisory fees $ 84.6 79.9 $ 251.1 237.0 Transaction fees & other 17.7 14.2 36.1 43.7 Incentive fees 8.0 17.5 27.9 58.7 Revenue $ 110.3 111.6 $ 315.1 339.4 Depreciation and amortization $ 1.8 1.7 $ 5.4 4.7 Equity earnings (losses) $ 8.5 14.9 $ (20.5 ) 30.3 Segment income $ 29.5 35.5 $ 28.8 93.0 The following table is a reconciliation of Segment income to consolidated Operating income. Three Months Ended September 30, Nine Months Ended September 30, (in millions) 2020 2019 2020 2019 Segment income - Americas $ 140.0 177.9 $ 277.1 359.1 Segment income (loss) - EMEA (1.9 ) 13.8 (55.8 ) (17.9 ) Segment income - APAC 35.8 31.5 57.4 59.5 Segment income - LaSalle 29.5 35.5 28.8 93.0 Less: Equity earnings (15.0 ) (17.1 ) (1.4 ) (32.3 ) Add: Restructuring and acquisition charges (33.5 ) (70.0 ) (75.8 ) (114.3 ) Operating income $ 154.9 171.6 $ 230.3 347.1

Business Combinations, Goodwill

Business Combinations, Goodwill and Other Intangible Assets	9 Months Ended
	Sep. 30, 2020
BUSINESS COMBINATIONS, GOODWILL AND OTHER INTANGIBLE ASSETS [Abstract]
Business Combinations, Goodwill and Other Intangible Assets	5. BUSINESS COMBINATIONS, GOODWILL AND OTHER INTANGIBLE ASSETS 2020 Business Combinations Activity During the nine months ended September 30, 2020 , we completed no new acquisitions and paid $58.5 million for deferred business acquisition and earn-out obligations for acquisitions completed in prior years. 2019 Business Combinations Activity During the nine months ended September 30, 2020 , we made no adjustments to our preliminary allocation of the purchase consideration for certain acquisitions completed in 2019. As of September 30, 2020 , we have completed our analysis to assign fair values to all the identifiable intangible and tangible assets acquired for our 2019 acquisitions. Earn-Out Payments ($ in millions) September 30, 2020 December 31, 2019 Number of acquisitions with earn-out payments subject to the achievement of certain performance criteria 42 44 Maximum earn-out payments (undiscounted) $ 221.3 $ 268.9 Short-term earn-out liabilities (fair value) 1 77.0 53.9 Long-term earn-out liabilities (fair value) 1 18.0 94.5 1 Included in Short-term and Long-term acquisition-related obligations on the Condensed Consolidated Balance Sheets. Assuming the achievement of the applicable performance criteria, we anticipate making these earn-out payments over the next five years. Refer to Note 8, Fair Value Measurements , and Note 11, Restructuring and Acquisition Charges , for additional discussion of our earn-out liabilities. Goodwill and Other Intangible Assets Goodwill and unamortized intangibles as of September 30, 2020 consisted of: (1) goodwill of $4,164.0 million , (2) identifiable intangibles of $601.9 million amortized over their remaining finite useful lives, and (3) $52.0 million of identifiable intangibles with indefinite useful lives that are not amortized. Notable portions of our goodwill and unamortized intangibles are denominated in currencies other than the U.S. dollar, which means a portion of the movements in the reported book value of these balances is attributable to movements in foreign currency exchange rates. During the three months ended September 30, 2020, as part of our annual impairment test of goodwill, we have considered qualitative and quantitative factors and determined it is not more-likely-than-not that the fair value of our Americas, Asia Pacific, and LaSalle reporting units are less than their carrying values. With respect to our EMEA reporting unit reporting, we performed step 1 of the goodwill impairment analysis which indicated the estimated fair value exceeded the carrying value by over 20%. In performing step 1, we relied on the discounted cash flow (“DCF”) method, an income approach, in determining the estimated fair value. Our DCF analysis relied on significant judgments and assumptions in determining the inputs, specifically, forecasted revenue growth, forecasted profitability margin, and the discount rate used to present value the estimated future cash flows. The following tables detail, by reporting segment, movements in goodwill. Real Estate Services (in millions) Americas EMEA Asia Pacific LaSalle Consolidated Balance as of December 31, 2019 $ 2,877.6 915.9 317.6 57.1 $ 4,168.2 Dispositions — (0.7 ) — — (0.7 ) Impact of exchange rate movements (1.1 ) (4.7 ) 2.6 (0.3 ) (3.5 ) Balance as of September 30, 2020 $ 2,876.5 910.5 320.2 56.8 $ 4,164.0 Real Estate Services (in millions) Americas EMEA Asia Pacific LaSalle Consolidated Balance as of December 31, 2018 $ 1,452.0 906.8 316.8 22.2 $ 2,697.8 Additions, net of adjustments 1,392.9 1.6 — 35.5 1,430.0 Dispositions — (0.9 ) — — (0.9 ) Impact of exchange rate movements 0.3 (37.6 ) (4.6 ) (1.8 ) (43.7 ) Balance as of September 30, 2019 $ 2,845.2 869.9 312.2 55.9 $ 4,083.2 The following tables detail, by reporting segment, movements in the gross carrying amount and accumulated amortization of our identifiable intangibles. MSRs Other Intangibles (in millions) Americas Americas EMEA Asia Pacific LaSalle Consolidated Gross Carrying Amount Balance as of December 31, 2019 $ 480.4 285.7 55.9 21.4 54.0 $ 897.4 Additions, net of adjustments (1) 77.9 — — 0.5 — 78.4 Adjustment for fully amortized intangibles (30.9 ) (14.1 ) (0.4 ) — — (45.4 ) Impact of exchange rate movements — (0.2 ) (1.5 ) 0.3 1.9 0.5 Balance as of September 30, 2020 $ 527.4 271.4 54.0 22.2 55.9 $ 930.9 Accumulated Amortization Balance as of December 31, 2019 $ (104.0 ) (68.3 ) (33.1 ) (6.7 ) (2.7 ) $ (214.8 ) Amortization, net (2) (65.5 ) (35.0 ) (5.2 ) (1.1 ) (2.0 ) (108.8 ) Adjustment for fully amortized intangibles 30.9 14.1 0.4 — — 45.4 Impact of exchange rate movements — 0.4 0.9 (0.1 ) — 1.2 Balance as of September 30, 2020 $ (138.6 ) (88.8 ) (37.0 ) (7.9 ) (4.7 ) $ (277.0 ) Net book value as of September 30, 2020 $ 388.8 182.6 17.0 14.3 51.2 $ 653.9 (1) Included in this amount for MSRs was (i) $15.3 million relating to prepayments/write-offs due to prepayments of the underlying obligation for which we assumed, acquired or retained the servicing rights and (ii) $1.9 million relating to a net impairment valuation allowance. (2) Amortization of MSRs is included in Revenue before reimbursements within the Condensed Consolidated Statements of Comprehensive Income. MSRs Other Intangibles (in millions) Americas Americas EMEA Asia Pacific LaSalle Consolidated Gross Carrying Amount Balance as of December 31, 2018 $ 266.2 90.0 83.1 23.5 43.9 $ 506.7 Additions, net of adjustments (1) 208.3 194.5 — — 10.3 413.1 Adjustment for fully amortized intangibles (21.8 ) (0.7 ) (22.1 ) (2.0 ) — (46.6 ) Impairments — (0.5 ) — — — (0.5 ) Impact of exchange rate movements — — (2.8 ) (0.8 ) (1.6 ) (5.2 ) Balance as of September 30, 2019 $ 452.7 283.3 58.2 20.7 52.6 $ 867.5 Accumulated Amortization Balance as of December 31, 2018 $ (72.4 ) (38.8 ) (51.8 ) (6.8 ) — $ (169.8 ) Amortization, net (2) (41.6 ) (18.9 ) (7.5 ) (1.6 ) (2.0 ) (71.6 ) Adjustment for fully amortized intangibles 21.8 0.7 22.1 2.0 — 46.6 Impairments — 0.5 — — — 0.5 Impact of exchange rate movements — — 2.2 0.2 — 2.4 Balance as of September 30, 2019 $ (92.2 ) (56.5 ) (35.0 ) (6.2 ) (2.0 ) $ (191.9 ) Net book value as of September 30, 2019 $ 360.5 226.8 23.2 14.5 50.6 $ 675.6 (1) Included in this amount for MSRs was $10.6 million relating to prepayments/write-offs due to prepayments of the underlying obligation for which we assumed, acquired or retained the servicing rights. (2) Amortization of MSRs is included in Revenue before reimbursements within the Condensed Consolidated Statements of Comprehensive Income. The remaining estimated future amortization expense of MSRs and other identifiable intangible assets, by year, as of September 30, 2020 , is presented in the following table. (in millions) MSRs Other Intangibles Total 2020 (remaining 3 months) $ 17.2 16.0 $ 33.2 2021 66.2 48.6 114.8 2022 59.3 42.9 102.2 2023 53.0 40.5 93.5 2024 45.4 36.2 81.6 2025 37.7 18.9 56.6 Thereafter 110.0 10.0 120.0 Total $ 388.8 213.1 $ 601.9

Investments in Real Estate Vent

Investments in Real Estate Ventures	9 Months Ended
	Sep. 30, 2020
Equity Method Investments and Joint Ventures [Abstract]
Investments in Real Estate Ventures	6. INVESTMENTS IN REAL ESTATE VENTURES As of September 30, 2020 and December 31, 2019 , we had Investments in real estate ventures of $389.6 million and $404.2 million , respectively. Approximately 90% of our investments, as of September 30, 2020 , are primarily (i) direct investments in 48 separate property or commingled funds, where we co-invest alongside our clients and for which we also have an advisory agreement and (ii) investments by JLL Spark in property-technology funds and early-stage companies. The remaining 10% of our Investments in real estate ventures, as of September 30, 2020 , were attributable to investment vehicles that use our capital and outside capital primarily provided by institutional investors to invest, primarily, in certain real estate ventures that own and operate real estate. Of our investments attributable to investment vehicles, the majority was invested in LaSalle Investment Company II ("LIC II"), in which we held an effective ownership interest of 48.78% . We have maximum potential unfunded commitments to direct investments or investment vehicles of $338.8 million as of September 30, 2020 . Of this amount, while we remain contractually obligated, we do not expect a call on the $60.4 million relating to our investment in LIC II as its fund life terminated in January 2020. We evaluate our less-than-wholly-owned investments to determine whether the underlying entities are classified as variable interest entities ("VIEs"); we assess each identified VIE to determine whether we are the primary beneficiary. We have determined that we are the primary beneficiary of certain VIEs and accordingly, we have consolidated such entities. The assets of the consolidated VIEs are available only for the settlement of the obligations of the respective entities and the mortgage loans of the consolidated VIEs are non-recourse to JLL. Summarized financial information for our consolidated VIEs is presented in the following tables. (in millions) September 30, 2020 December 31, 2019 Property and equipment, net $ 132.9 126.3 Investments in real estate ventures 9.2 13.2 Other assets 9.6 14.3 Total assets $ 151.7 153.8 Other current liabilities $ 2.6 3.2 Mortgage indebtedness (included in Other liabilities) 71.3 69.7 Total liabilities 73.9 72.9 Members' equity (included in Noncontrolling interest) 77.8 80.9 Total liabilities and members' equity $ 151.7 153.8 Three Months Ended September 30, Nine Months Ended September 30, (in millions) 2020 2019 2020 2019 Revenue $ 3.6 1.9 $ 10.8 4.9 Operating and other expenses (3.7 ) (2.1 ) (11.9 ) (5.3 ) Net gains on sale of investments 1 3.1 — 15.3 — Net income (loss) $ 3.0 (0.2 ) $ 14.2 (0.4 ) (1) $12.2 million of the year-to-date gain is included in Equity earnings; the remaining $3.1 million is included in Other income. We allocate the members' equity and net income of the consolidated VIEs to the noncontrolling interest holders as Noncontrolling interest on our Condensed Consolidated Balance Sheets and as Net income attributable to noncontrolling interest in our Condensed Consolidated Statements of Comprehensive Income, respectively. Impairment There were no significant other-than-temporary impairment charges on Investments in real estate ventures for the nine months ended September 30, 2020 and 2019 . Fair Value We report a majority of our investments in real estate ventures at fair value. For such investments, we increase or decrease our investment each reporting period by the change in the fair value and we report these fair value adjustments in our Condensed Consolidated Statements of Comprehensive Income within Equity earnings. The table below shows the movement in our investments in real estate ventures reported at fair value. (in millions) 2020 2019 Fair value investments as of January 1, $ 328.6 247.3 Investments 36.8 67.1 Distributions (58.8 ) (39.2 ) Change in fair value, net (9.1 ) 29.8 Foreign currency translation adjustments, net 1.5 (0.8 ) Fair value investments as of September 30, $ 299.0 304.2 See Note 8, Fair Value Measurements , for additional discussion of our investments in real estate ventures reported at fair value.

Stock-based Compensation

Stock-based Compensation	9 Months Ended
	Sep. 30, 2020
Share-based Payment Arrangement [Abstract]
Stock-based Compensation	7. STOCK-BASED COMPENSATION Stock Unit Awards Restricted stock unit ("RSU") and performance stock unit ("PSU") awards activity is presented in the following tables. RSU Shares PSU Shares Total Shares Weighted Average Weighted Average Unvested as of June 30, 2020 1,343.2 558.8 1,902.0 $ 137.93 2.01 Granted 11.2 4.4 15.6 107.51 Vested (213.5 ) — (213.5 ) 140.38 Forfeited (13.0 ) (4.5 ) (17.5 ) 134.03 Unvested as of September 30, 2020 1,127.9 558.7 1,686.6 $ 137.49 1.85 Unvested as of June 30, 2019 436.7 259.6 696.3 $ 144.17 2.25 Granted 1,130.1 — 1,130.1 141.14 Vested (45.8 ) — (45.8 ) 122.48 Forfeited (8.1 ) — (8.1 ) 138.96 Unvested as of September 30, 2019 1,512.9 259.6 1,772.5 $ 142.82 2.59 RSU Shares PSU Shares Total Shares Weighted Average Weighted Average Remaining (in years) Unvested as of December 31, 2019 1,532.3 286.8 1,819.1 $ 141.51 2.39 Granted 173.1 276.4 449.5 114.19 Vested (548.4 ) — (548.4 ) 137.92 Forfeited (29.1 ) (4.5 ) (33.6 ) 136.96 Unvested as of September 30, 2020 1,127.9 558.7 1,686.6 $ 137.49 1.85 Unvested as of December 31, 2018 559.6 93.1 652.7 $ 131.32 2.02 Granted 1,243.4 166.9 1,410.3 149.22 Vested (268.3 ) — (268.3 ) 116.25 Forfeited (21.8 ) (0.4 ) (22.2 ) 134.54 Unvested as of September 30, 2019 1,512.9 259.6 1,772.5 $ 142.82 2.59 As of September 30, 2020 , we had $84.3 million of unamortized deferred compensation related to unvested RSUs and PSUs, which we anticipate recognizing over varying periods into 2024 ; $41.5 million relates to the awards issued in conjunction with the HFF acquisition.

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2020
Fair Value Disclosures [Abstract]
Fair Value Measurements	8. FAIR VALUE MEASUREMENTS We measure certain assets and liabilities in accordance with ASC 820, Fair Value Measurements and Disclosures , which defines fair value as the price that would be received for an asset, or paid to transfer a liability, in an orderly transaction between market participants on the measurement date. In addition, it establishes a framework for measuring fair value according to the following three-tier fair value hierarchy: • Level 1 - Quoted prices for identical assets or liabilities in active markets accessible as of the measurement date; • Level 2 - Inputs, other than quoted prices in active markets, that are observable either directly or indirectly; and • Level 3 - Unobservable inputs in which there is little or no market data, which require the reporting entity to develop its own assumptions. Financial Instruments Our financial instruments include Cash and cash equivalents, Trade receivables, Notes and other receivables, Reimbursable receivables, Warehouse receivables, restricted cash, contract assets, Accounts payable, Reimbursable payables, Short-term borrowings, contract liabilities, Warehouse facilities, Credit facility, Long-term debt, and foreign currency forward contracts. The carrying amounts of Cash and cash equivalents, Trade receivables, Notes and other receivables, Reimbursable receivables, restricted cash, contract assets, Accounts payable, Reimbursable payables, contract liabilities, and the Warehouse facilities approximate their estimated fair values due to the short-term nature of these instruments. The carrying values of our Credit facility and Short-term borrowings approximate their estimated fair values given the variable interest rate terms and market spreads. We estimated the fair value of our Long-term debt as $686.1 million and $685.9 million as of September 30, 2020 and December 31, 2019 , respectively, using dealer quotes that are Level 2 inputs in the fair value hierarchy. The carrying value of our Long-term debt was $682.9 million and $664.6 million as of September 30, 2020 and December 31, 2019 , respectively, and included debt issuance costs of $2.7 million and $3.1 million , respectively. Investments in Real Estate Ventures at Fair Value - Net Asset Value ("NAV") We report a significant portion of our investments in real estate ventures at fair value. For such investments, we increase or decrease our investment each reporting period by the change in the fair value and we report these fair value adjustments in our Condensed Consolidated Statements of Comprehensive Income within Equity earnings. For the majority of our investments reported at fair value, we estimate the fair value using the NAV per share (or its equivalent) our investees provide. Critical inputs to NAV estimates included valuations of the underlying real estate assets and borrowings, which incorporate investment-specific assumptions such as discount rates, capitalization rates, rental and expense growth rates, and asset-specific market borrowing rates. As of September 30, 2020 and December 31, 2019 , investments in real estate ventures at fair value using NAV were $192.4 million and $224.8 million , respectively. As these investments are not required to be classified in the fair value hierarchy, they have been excluded from the following table. Recurring Fair Value Measurements The following table categorizes by level in the fair value hierarchy the estimated fair value of our assets and liabilities measured at fair value on a recurring basis. September 30, 2020 December 31, 2019 (in millions) Level 1 Level 2 Level 3 Level 1 Level 2 Level 3 Assets Investments in real estate ventures - fair value $ 56.4 — 50.2 69.4 — 34.4 Foreign currency forward contracts receivable — 3.2 — — 10.5 — Warehouse receivables — 1,750.6 — — 527.1 — Deferred compensation plan assets — 410.7 — — 349.9 — Mortgage banking derivative assets — — 87.0 — — 36.1 Total assets at fair value $ 56.4 2,164.5 137.2 69.4 887.5 70.5 Liabilities Foreign currency forward contracts payable — 10.5 — — 4.4 — Deferred compensation plan liabilities — 388.4 — — 346.1 — Earn-out liabilities — — 95.0 — — 148.5 Mortgage banking derivative liabilities — — 80.8 — — 25.9 Total liabilities at fair value $ — 398.9 175.8 — 350.5 174.4 Investments in Real Estate Ventures We classify one investment as Level 1 in the fair value hierarchy as a quoted price is readily available. We increase or decrease our investment each reporting period by the change in the fair value of the investment. We report these fair value adjustments in our Condensed Consolidated Statements of Comprehensive Income within Equity earnings. Investments classified as Level 3 in the fair value hierarchy represent investments in early-stage non-public entities where we elected the fair value option. The carrying value was deemed to approximate fair value for the majority of these investments due to the proximity of the investment date to the balance sheet date as well as consideration of investee-level performance updates. To the extent there are changes in fair value, a result of pricing in subsequent funding rounds or changes in business strategy, for example, we recognize such changes through Equity earnings. Foreign Currency Forward Contracts We regularly use foreign currency forward contracts to manage our currency exchange rate risk related to intercompany lending and cash management practices. We determine the fair values of these contracts based on current market rates. The inputs for these valuations are Level 2 inputs in the fair value hierarchy. As of September 30, 2020 and December 31, 2019 , these contracts had a gross notional value of $2.03 billion ( $1.05 billion on a net basis) and $2.30 billion ( $1.05 billion on a net basis), respectively. We recognize gains and losses from revaluation of these contracts as a component of Operating, administrative and other expense. They are offset by the gains and losses we recognize on the revaluation of intercompany loans and other foreign currency balances. The impact to net income was not significant for the nine months ended September 30, 2020 or 2019 . We record the asset and liability positions for our foreign currency forward contracts based on the net payable or net receivable position with the financial institutions from which we purchase these contracts. The $3.2 million asset as of September 30, 2020 , was composed of gross contracts with receivable positions of $3.4 million and payable positions of $0.2 million . The $10.5 million liability as of September 30, 2020 , was composed of gross contracts with receivable positions of $1.9 million and payable positions of $12.4 million . As of December 31, 2019 , the $10.5 million asset was composed of gross contracts with receivable positions of $10.6 million and payable positions of $0.1 million . The $4.4 million liability as of December 31, 2019 , was composed of gross contracts with receivable positions of $0.8 million and payable positions of $5.2 million . Warehouse Receivables As of September 30, 2020 and December 31, 2019 , all of our Warehouse receivables were under commitment to be purchased by government-sponsored enterprises ("GSEs") or by a qualifying investor as part of a U.S. government or GSE mortgage-backed security program. Deferred Compensation Plan We maintain a deferred compensation plan for certain of our U.S. employees that allows them to defer portions of their compensation. We recorded this plan on our Condensed Consolidated Balance Sheet as of September 30, 2020 , as Deferred compensation plan assets of $410.7 million , long-term deferred compensation plan liabilities of $388.4 million , included in Deferred compensation, and as a reduction of equity, Shares held in trust, of $5.6 million . We recorded this plan on our Condensed Consolidated Balance Sheet as of December 31, 2019 , as Deferred compensation plan assets of $349.9 million , long-term deferred compensation plan liabilities of $346.1 million , included in Deferred compensation, and as a reduction of equity, Shares held in trust, of $5.7 million . Earn-Out Liabilities We classify our earn-out liabilities within Level 3 in the fair value hierarchy because the inputs we use to develop the estimated fair value include unobservable inputs. See Note 5, Business Combinations, Goodwill and Other Intangible Assets , for additional discussion of our earn-out liabilities. Mortgage Banking Derivatives Both our interest rate lock commitments to prospective borrowers and forward sale contracts with prospective investors are undesignated derivatives and considered Level 3 valuations due to significant unobservable inputs related to counterparty credit risk. An increase in counterparty credit risk assumptions would result in a lower fair value measurement. The tables below present a reconciliation for assets and liabilities measured at fair value on a recurring basis using significant unobservable inputs (Level 3). Balance as of June 30, 2020 Net change in fair value Foreign CTA 1 Purchases / Additions Settlements Balance as of September 30, 2020 Investments in real estate ventures $ 44.3 4.3 — 1.6 — $ 50.2 Mortgage banking derivative assets and liabilities, net (5.5 ) (2.6 ) — 48.2 (33.9 ) 6.2 Earn-out liabilities 97.8 (0.6 ) 0.7 — (2.9 ) 95.0 Balance as of June 30, 2019 Net change in fair value Foreign CTA 1 Purchases / Additions Settlements Balance as of September 30, 2019 Investments in real estate ventures $ 20.0 0.8 — 6.5 (0.8 ) $ 26.5 Mortgage banking derivative assets and liabilities, net (1.3 ) (7.1 ) — 45.3 (9.9 ) 27.0 Earn-out liabilities 180.3 0.7 (2.4 ) — (4.8 ) 173.8 (in millions) Balance as of December 31, 2019 Net change in fair value Foreign CTA 1 Purchases / Additions Settlements Balance as of September 30, 2020 Investments in real estate ventures $ 34.4 6.8 — 9.0 — $ 50.2 Mortgage banking derivative assets and liabilities, net 10.2 (93.2 ) — 112.9 (23.7 ) 6.2 Earn-out liabilities 148.5 (8.2 ) (0.2 ) — (45.1 ) 95.0 (in millions) Balance as of December 31, 2018 Net change in fair value Foreign CTA 1 Purchases / Additions Settlements Balance as of June 30, 2019 Investments in real estate ventures $ 11.5 0.8 — 15.0 (0.8 ) $ 26.5 Mortgage banking derivative assets and liabilities, net 6.3 (28.8 ) — 77.8 (28.3 ) 27.0 Earn-out liabilities 192.0 20.7 (2.6 ) 1.5 (37.8 ) 173.8 1 CTA: Currency translation adjustments Net change in fair value, included in the tables above, is reported in Net income as follows. Category of Assets/Liabilities using Unobservable Inputs Condensed Consolidated Statements of Comprehensive Income Account Caption Earn-out liabilities (Short-term and Long-term) Restructuring and acquisition charges Investments in real estate ventures Equity earnings Other current assets - Mortgage banking derivative assets Revenue before reimbursements Other current liabilities - Mortgage banking derivative liabilities Revenue before reimbursements Non-Recurring Fair Value Measurements We review our investments in real estate ventures, except those investments otherwise reported at fair value, on a quarterly basis, or as otherwise deemed necessary, for indications of whether we may be unable to recover the carrying value of our investments and whether such investments are other-than-temporarily impaired. When the carrying amount of the investment is in excess of the estimated future undiscounted cash flows, we use a discounted cash flow approach or other acceptable method to determine the fair value of the investment in computing the amount of the impairment. Our determination of fair value primarily relies on Level 3 inputs. We did not recognize any significant investment-level impairment losses during either of the three or nine months ended September 30, 2020 or 2019 . See Note 6, Investments in Real Estate Ventures , for additional information, including information related to impairment charges recorded at the investee level.

Debt

Debt	9 Months Ended
	Sep. 30, 2020
Debt Disclosure [Abstract]
Debt	9. DEBT Short-term borrowings and long-term debt obligations are composed of the following. (in millions) September 30, 2020 December 31, 2019 Short-term borrowings: Local overdraft facilities $ 12.2 44.8 Other short-term borrowings 94.2 75.3 Total short-term borrowings $ 106.4 120.1 Credit facility, net of debt issuance costs of $9.6 and $12.3 390.4 512.7 Long-term senior notes, 4.4%, face amount of $275.0, due November 2022, net of debt issuance costs of $0.8 and $1.2 274.2 273.8 Long-term senior notes, 1.96%, face amount of €175.0, due June 2027, net of debt issuance costs of $0.9 and $0.9 204.4 195.4 Long-term senior notes, 2.21%, face amount of €175.0, due June 2029, net of debt issuance costs of $1.0 and $1.0 204.3 195.4 Total debt $ 1,179.7 1,297.4 Credit Facility We have a $2.75 billion unsecured revolving credit facility (the "Facility") that matures on May 17, 2023 . Pricing on the Facility ranges from LIBOR plus 0.875% to 1.35% , with pricing as of September 30, 2020 , at LIBOR plus 0.95% . In addition to outstanding borrowings under the Facility presented in the above table, we had outstanding letters of credit under the Facility of $0.7 million and $0.8 million as of September 30, 2020 and December 31, 2019 , respectively. The following tables provides additional information on our Facility. Three Months Ended September 30, Nine Months Ended September 30, ($ in millions) 2020 2019 2020 2019 Average outstanding borrowings under the Facility $ 758.9 1,408.5 $ 1,014.3 763.9 Effective interest rate on the Facility 1.1 % 3.1 % 1.6 % 3.2 % We will continue to use the Facility for, but not limited to, business acquisitions, working capital needs (including payment of accrued incentive compensation), co-investment activities, dividend payments, share repurchases and capital expenditures. Short-Term Borrowings and Long-Term Debt In addition to our Facility, we have the capacity to borrow up to an additional $85.9 million under local overdraft facilities. Amounts outstanding are presented in the debt table above. As of September 30, 2020 , our issuer and senior unsecured ratings are investment grade: Baa1 from Moody’s Investors Service, Inc. and BBB+ from Standard & Poor’s Ratings Services. Covenants Our Facility and senior notes are subject to customary financial and other covenants, including cash interest coverage ratios and leverage ratios, as well as event of default conditions. We remained in compliance with all covenants as of September 30, 2020 . Warehouse Facilities September 30, 2020 December 31, 2019 ($ in millions) Outstanding Balance Maximum Capacity Outstanding Balance Maximum Capacity Warehouse Facilities: LIBOR plus 1.15%, October 21, 2020 1 $ 300.2 375.0 104.4 375.0 LIBOR plus 1.40%, expires September 18, 2021 2 1,016.0 1,200.0 184.8 775.0 LIBOR plus 1.40%, expires August 27, 2021 3 85.1 200.0 11.4 100.0 Fannie Mae ASAP 4 program, LIBOR plus 1.15% 84.3 n/a 53.6 n/a LIBOR plus 1.25% 5 239.2 500.0 151.6 1,000.0 LIBOR plus 1.25% — — 11.0 175.0 Gross warehouse facilities 1,724.8 2,275.0 516.8 2,425.0 Debt issuance costs (1.0 ) n/a (0.9 ) n/a Total warehouse facilities $ 1,723.8 2,275.0 515.9 2,425.0 1 In the third quarter of 2020, JLL extended the Warehouse facility; previously, the facility had a maturity date of September 21, 2020. In October 2020, JLL extended the Warehouse facility to September 20, 2021 with a maximum capacity of $400 million and an increase to the interest rate (to LIBOR plus 1.40%). 2 In the third quarter of 2020, JLL extended the Warehouse facility with an increase to the interest rate; previously, the facility had a maturity date of September 19, 2020 and an interest rate of LIBOR plus 1.15%. 3 In the third quarter of 2020, JLL extended the Warehouse facility with an increase to the interest rate; previously, the facility had a maturity date of August 31, 2020 and an interest rate of LIBOR plus 1.15%. 4 As Soon As Pooled ("ASAP") funding program 5 In the third quarter of 2020, the maximum capacity was reduced from $1.0 billion to $500 million. We have lines of credit established for the sole purpose of funding our Warehouse receivables. These lines of credit exist with financial institutions and are secured by the related warehouse receivables. Pursuant to these warehouse facilities, we are required to comply with certain financial covenants regarding (1) minimum net worth, (2) minimum servicing-related loans, and (3) minimum adjusted leverage ratios. We remained in compliance with all covenants under our Warehouse facilities as of September 30, 2020 .

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2020
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	10. COMMITMENTS AND CONTINGENCIES We are a defendant in various litigation matters arising in the ordinary course of business, some of which involve claims for damages that are substantial in amount. When a potential loss event occurs, we estimate the ultimate cost of the claim and accrue the amount in Other current and long-term liabilities on our Condensed Consolidated Balance Sheets when probable and estimable. In addition, we have established receivables from third-party insurance providers for claim amounts in excess of the risk retained by our captive insurance company. In total, these receivables were $41.0 million and $37.7 million as of September 30, 2020 and December 31, 2019 , respectively, and are included in Notes and other receivables and Long-term receivables on our Condensed Consolidated Balance Sheets. The following table shows the professional indemnity accrual activity and related payments. (in millions) December 31, 2019 $ 38.1 New claims 5.8 Prior year claims adjustments (including foreign currency changes) 0.8 Claims paid — September 30, 2020 $ 44.7 December 31, 2018 $ 43.1 New claims 0.1 Prior year claims adjustments (including foreign currency changes) (4.4 ) Claims paid (1.1 ) September 30, 2019 $ 37.7 As a participant in the DUS program, we retain a portion of the risk of loss for loans that are originated and sold under the DUS program. Net losses on defaulted loans are shared with Fannie Mae based upon established loss-sharing ratios. Generally, we share approximately one-third of incurred losses, subject to a cap of 20% of the principal balance of the mortgage at origination. As of September 30, 2020 and December 31, 2019 , we had loans subject to such loss-sharing arrangements with an aggregate unpaid principal balance of $11.0 billion and $9.7 billion , respectively. For all DUS program loans with loss-sharing obligations, we record a non-contingent liability equal to the estimated fair value of the guarantee obligations undertaken upon sale of the loan, which reduces our gain on sale of the loan. Subsequently, this liability is amortized over the estimated life of the loan and recognized as Revenue on the Condensed Consolidated Statements of Comprehensive Income. As of September 30, 2020 and December 31, 2019 , the loss-sharing guarantee obligations were $20.7 million and $20.6 million , respectively, and are included in Other liabilities on our Condensed Consolidated Balance Sheets. There were no loan losses incurred for the three and nine months ended September 30, 2020 and 2019 .

Restructuring and Acquisition C

Restructuring and Acquisition Charges	9 Months Ended
	Sep. 30, 2020
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Activities Disclosure [Text Block]	11. RESTRUCTURING AND ACQUISITION CHARGES Restructuring and acquisition charges include cash and non-cash expenses. Cash-based charges primarily consist of (1) severance and employment-related charges, including those related to external service providers, incurred in conjunction with a structural business shift, which can be represented by a notable change in headcount, change in leadership, or transformation of business processes, (2) acquisition, transaction and integration-related charges, and (3) other restructuring including lease exit charges. Non-cash charges include (1) stock-based compensation expense for retention awards issued in conjunction with the HFF acquisition and (2) fair value adjustments to earn-out liabilities relating to prior-period acquisition activity. Restructuring and acquisition charges are presented in table below. Three Months Ended September 30, Nine Months Ended September 30, (in millions) 2020 2019 2020 2019 Severance and other employment-related charges $ 19.3 7.2 $ 27.6 17.6 Restructuring, pre-acquisition and post-acquisition charges 8.6 48.1 25.9 62.0 Stock-based compensation expense for HFF retention awards 6.2 14.0 30.5 14.0 Fair value adjustments to earn-out liabilities (0.6 ) 0.7 (8.2 ) 20.7 Restructuring and acquisition charges $ 33.5 70.0 $ 75.8 114.3 The following tables show the accrual activity and payments relating to cash-based Restructuring and acquisition charges. (in millions) Severance & Employment-Related Lease Exit Restructuring, Acquisition and Total December 31, 2019 $ 24.3 8.4 3.8 $ 36.5 Accruals 27.6 9.3 16.6 53.5 Payments made (22.1 ) (16.0 ) (20.4 ) (58.5 ) September 30, 2020 $ 29.8 1.7 — $ 31.5 (in millions) Severance & Employment-Related Lease Other Restructuring, Total December 31, 2018 $ 14.0 0.6 0.5 $ 15.1 Accruals 17.6 5.8 56.2 79.6 Payments made (21.2 ) (1.5 ) (54.8 ) (77.5 ) September 30, 2019 $ 10.4 4.9 1.9 $ 17.2 We expect the majority of accrued severance and other accrued acquisition costs as of September 30, 2020 will be paid during the next twelve months. Lease exit payments depend on the terms of various leases, which extend as far out as 2022. HFF Acquisition Included in Restructuring and acquisition charges were $13.8 million and $55.2 million , respectively, for the three and nine months ended September 30, 2020 compared to $60.1 million and $69.8 million , respectively, for the three and nine months ended September 30, 2019 of charges relating to the acquisition and integration of HFF (including transaction/deal costs, retention and severance expense, early lease termination costs, and other integration expenses). During the integration of HFF, we expect to incur significant charges over the two years following the acquisition in an effort to maximize the value of the combined organization. We expect to recognize approximately $100 million of expense over this two-year window relating to retention awards which have already been paid or granted (in the case of RSUs). In addition, we may incur other costs in connection with the integration including, but not limited to, lease termination charges and other employee-related costs, but are unable to estimate these amounts. We anticipate that other than RSU retention awards granted, substantially all of these cumulative charges will result in cash expenditures.

Accumulated Other Comprehensive

Accumulated Other Comprehensive Income (Loss) by Component	9 Months Ended
	Sep. 30, 2020
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Accumulated Other Comprehensive Income (Loss) by Component	12. ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) BY COMPONENT The tables below present the changes in Accumulated other comprehensive income (loss) ("AOCI") by component. For pension and postretirement benefits, we report amounts reclassified from AOCI relating to employer service cost in Compensation and benefits within the Condensed Consolidated Statements of Comprehensive Income. All other reclassifications relating to pension and postretirement benefits are reported within Other income. (in millions) Pension and postretirement benefit Cumulative foreign currency translation adjustment Total Balance as of June 30, 2020 $ (72.0 ) (465.4 ) $ (537.4 ) Other comprehensive income before reclassification — 59.3 59.3 Amounts reclassified from AOCI after tax expense of $ - , $ - and $ - 0.7 — 0.7 Other comprehensive income after tax expense of $ - , $ - and $ - 0.7 59.3 60.0 Balance as of September 30, 2020 $ (71.3 ) (406.1 ) $ (477.4 ) (in millions) Pension and postretirement benefit Cumulative foreign currency translation adjustment Total Balance as of June 30, 2019 $ (59.2 ) (390.8 ) $ (450.0 ) Other comprehensive loss before reclassification — (34.6 ) (34.6 ) Amounts reclassified from AOCI after tax expense of $ - , $ - and $ - 0.1 — 0.1 Other comprehensive loss after tax expense of $ - , $ - and $ - 0.1 (34.6 ) (34.5 ) Balance as of September 30, 2019 $ (59.1 ) (425.4 ) $ (484.5 ) (in millions) Pension and postretirement benefit Cumulative foreign currency translation adjustment Total Balance as of December 31, 2019 $ (72.0 ) (355.8 ) $ (427.8 ) Other comprehensive loss before reclassification — (50.3 ) (50.3 ) Amounts reclassified from AOCI after tax expense of $ - , $ - and $ - 0.7 — 0.7 Other comprehensive loss after tax expense of $ - , $ - and $ - 0.7 (50.3 ) (49.6 ) Balance as of September 30, 2020 $ (71.3 ) (406.1 ) $ (477.4 ) (in millions) Pension and postretirement benefit Cumulative foreign currency translation adjustment Total Balance as of December 31, 2018 $ (57.4 ) (398.8 ) $ (456.2 ) Other comprehensive income before reclassification — (26.6 ) (26.6 ) Amounts reclassified from AOCI after tax expense of $ - , $ - and $ - (1.7 ) — (1.7 ) Other comprehensive (loss) income after tax expense of $ - , $ - and $ - (1.7 ) (26.6 ) (28.3 ) Balance as of September 30, 2019 $ (59.1 ) (425.4 ) $ (484.5 )

New Accounting Standards New _2

New Accounting Standards New Accounting Standards (Policies)	9 Months Ended
	Sep. 30, 2020
Text Block [Abstract]
Accounting Standards Update and Change in Accounting Principle [Text Block]	2. NEW ACCOUNTING STANDARDS Recently adopted accounting guidance In June 2016, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") No. 2016-13, Financial Instruments - Credit Losses (ASC Topic 326) , which created a new framework to evaluate financial instruments, such as trade receivables, for expected credit losses. This new framework replaced the existing incurred loss approach and is expected to result in more timely recognition of credit losses. On January 1, 2020, we adopted ASU No. 2016-13 using a modified-retrospective approach, as required by the ASU. The adoption impacted our methodology of reserving for (i) Trade receivables, (ii) other receivable-related financial assets, specifically contract assets, and (iii) off-balance sheet credit exposures within the scope of this ASU. Specifically, we evaluated our historical reserve balances for Trade receivables and the related write-off activity and developed a forward-looking process for adoption. We also evaluated our loss-sharing guarantee obligation for certain mortgage loans we originate, sell and retain the servicing rights. The following sections discuss our updated reserve methodologies. Trade Receivables We estimate an allowance to provide for uncollectible accounts receivable, which is applied upon recognition of the receivable. We base this estimate on historical experience combined with a review of the receivable aging, current and expected economic conditions, and client credit quality. The estimate also includes specifically identified amounts for which payment has become unlikely. As trade receivables are due within one year, changes to economic conditions are not expected to have a significant impact on our estimate of expected credit losses. However, we will monitor economic conditions on a quarterly basis to determine if any adjustments are deemed necessary. Notes and Other Receivables and Long-Term Receivables We make ongoing assessments of the collectability of outstanding Notes and other receivables and Long-term receivables, considering both objective and subjective factors such as the aging profile of outstanding balances, the contractual terms of repayment, and credit quality. Aspects of credit quality considered in our assessments of collectability include historical experience, current and expected economic conditions, and our broader business relationship with the obligor. We record an allowance against the outstanding balance when our assessments determine payment has become unlikely. After all collection efforts have been exhausted by management, the outstanding balance is written off against the reserve. Historically, credit quality deterioration to the point of impairment or non-performance in our Notes and other receivables and Long-term receivables has been limited and has not had a material impact on the Condensed Consolidated Financial Statements. Reimbursable Receivables We record an allowance based on specific identification of an uncollectible reimbursable receivable, considering current and future economic conditions as well as client credit quality. Historically, we have not experienced any material collection issues and, as such, have not applied a formulaic reserve to these receivables. Contract Assets Contract assets include amounts recognized as revenue for which we are not yet entitled to payment for reasons other than the passage of time, but that do not constrain revenue recognition. Historically, we have not recognized a provision for contract assets. Under ASC Topic 326, we include Contract assets in our reserving process and assess the risk of loss similar to our methodology for Trade receivables, since Contract assets are reclassified to Trade receivables when we become entitled to payment. Accordingly, a reserve is applied upon recognition of the contract asset. Financial Guarantees Certain loans we originate and sell under the Fannie Mae Delegated Underwriting and Servicing (“DUS”) program retain a percentage of the risk of loss. This loss-sharing aspect of the program represents an off-balance sheet credit exposure, and we have established a contingent reserve ("loan loss guarantee reserve") for this risk in accordance with ASC Topic 326. To estimate the reserve, we use a model that analyzes historical losses, current and expected economic conditions, and reasonable and supportable forecasts. The model also considers specific details of the underlying property used as collateral, such as occupancy and financial performance. The loan loss guarantee reserve is calculated on an individual loan level. As of September 30, 2020, the loan loss guarantee reserve was $45.7 million and was included within Other liabilities on the Condensed Consolidated Balance Sheets. This balance reflected a notable increase from our opening balance (reflected in the table below) as a result of incorporating, into our model, economic conditions and projections related to the COVID-19 pandemic. The loss-sharing guarantee obligation (in accordance with ASC Topic 460, Guarantees ) represents the non-contingent obligation incurred as a result of issuing a loss-sharing guarantee as part of our participation in the DUS program and is separate from the loan loss guarantee reserve discussed above. See Note 10, Commitments and Contingencies , for further information on the DUS program and the loss-sharing guarantee obligation. The following table details the cumulative impact to retained earnings upon adoption of ASC Topic 326. Published Adjustment due to As Reported Under December 31, 2019 adoption of ASC Topic 326 on January 1, 2020 (in millions) (audited) ASC Topic 326 (unaudited) Assets Allowance for trade receivables $ (68.1 ) (3.6 ) $ (71.7 ) Deferred tax assets, net 245.4 5.5 250.9 Allowance for contract assets (1) — (1.7 ) (1.7 ) Liabilities and equity Loan loss guarantee reserve (2) $ — 15.1 $ 15.1 Retained earnings 3,588.3 (14.9 ) 3,573.4 1 The portion of the allowance for long-term contract assets is included within Other assets on the Condensed Consolidated Balance Sheets. 2 Included within Other liabilities on the Condensed Consolidated Balance Sheets

New Accounting Standards Cumula

New Accounting Standards Cumulative impact upon adoption of ASC Topic 326 (Tables)	Jan. 01, 2020
Cumulative Impact ASC Topic 326 [Line Items]
Cumulative Impact ASC Topic 326 [Table Text Block]	The following table details the cumulative impact to retained earnings upon adoption of ASC Topic 326. Published Adjustment due to As Reported Under December 31, 2019 adoption of ASC Topic 326 on January 1, 2020 (in millions) (audited) ASC Topic 326 (unaudited) Assets Allowance for trade receivables $ (68.1 ) (3.6 ) $ (71.7 ) Deferred tax assets, net 245.4 5.5 250.9 Allowance for contract assets (1) — (1.7 ) (1.7 ) Liabilities and equity Loan loss guarantee reserve (2) $ — 15.1 $ 15.1 Retained earnings 3,588.3 (14.9 ) 3,573.4 1 The portion of the allowance for long-term contract assets is included within Other assets on the Condensed Consolidated Balance Sheets. 2 Included within Other liabilities on the Condensed Consolidated Balance Sheets

Revenue Recognition Disaggregat

Revenue Recognition Disaggregation of Revenue (Tables)	9 Months Ended
	Sep. 30, 2020
Disaggregation of Revenue [Line Items]
Disaggregation of Revenue [Table Text Block]	Such revenue was included entirely within Americas Capital Markets and is presented below. Three Months Ended September 30, Nine months ended September 30, (in millions) 2020 2019 2020 2019 Revenue excluded from scope of ASC Topic 606 $ 72.0 74.3 $ 174.7 137.6
Contract with Customer, Contract Asset, Contract Liability, and Receivable [Table Text Block]	Such contract assets and liabilities are presented below. (in millions) September 30, 2020 December 31, 2019 Contract assets, gross $ 389.8 419.3 Contract asset allowance (3.2 ) — Contract assets, net $ 386.6 419.3 Contract liabilities $ 85.7 87.7

Business Segments (Tables)

Business Segments (Tables)	9 Months Ended
	Sep. 30, 2020
Segment Reporting [Abstract]
Summarized Unaudited Financial Information by Business Segments	Summarized financial information by business segment is as follows. Three Months Ended September 30, Nine Months Ended September 30, (in millions) 2020 2019 2020 2019 Americas Leasing $ 325.2 472.7 $ 1,022.2 1,354.3 Capital Markets 190.8 323.2 579.0 553.1 Property & Facility Management 1,433.3 1,386.3 4,331.6 4,119.2 Project & Development Services 336.2 406.0 917.9 1,091.5 Advisory, Consulting and Other 95.3 99.4 282.2 283.2 Revenue $ 2,380.8 2,687.6 $ 7,132.9 7,401.3 Depreciation and amortization $ 36.4 35.3 $ 112.9 88.9 Equity earnings $ 4.8 1.5 $ 20.4 1.6 Segment income $ 140.0 177.9 $ 277.1 359.1 EMEA Leasing $ 58.5 72.2 $ 153.3 190.3 Capital Markets 73.3 106.2 196.5 248.7 Property & Facility Management 348.7 387.1 1,044.2 1,137.0 Project & Development Services 190.8 234.2 558.3 633.9 Advisory, Consulting and Other 72.5 62.9 173.6 194.4 Revenue $ 743.8 862.6 $ 2,125.9 2,404.3 Depreciation and amortization $ 9.8 10.1 $ 28.0 32.7 Equity earnings (losses) $ 0.8 — $ 0.8 (1.0 ) Segment income (loss) $ (1.9 ) 13.8 $ (55.8 ) (17.9 ) Asia Pacific Leasing $ 46.6 59.4 $ 105.8 161.5 Capital Markets 20.4 50.6 66.1 128.2 Property & Facility Management 521.3 539.4 1,568.5 1,630.6 Project & Development Services 104.5 145.7 296.5 393.9 Advisory, Consulting and Other 50.4 38.7 133.7 123.5 Revenue $ 743.2 833.8 $ 2,170.6 2,437.7 Depreciation and amortization $ 6.9 6.5 $ 20.5 19.3 Equity earnings $ 0.9 0.7 $ 0.7 1.4 Segment income $ 35.8 31.5 $ 57.4 59.5 LaSalle Advisory fees $ 84.6 79.9 $ 251.1 237.0 Transaction fees & other 17.7 14.2 36.1 43.7 Incentive fees 8.0 17.5 27.9 58.7 Revenue $ 110.3 111.6 $ 315.1 339.4 Depreciation and amortization $ 1.8 1.7 $ 5.4 4.7 Equity earnings (losses) $ 8.5 14.9 $ (20.5 ) 30.3 Segment income $ 29.5 35.5 $ 28.8 93.0 The following table is a reconciliation of Segment income to consolidated Operating income. Three Months Ended September 30, Nine Months Ended September 30, (in millions) 2020 2019 2020 2019 Segment income - Americas $ 140.0 177.9 $ 277.1 359.1 Segment income (loss) - EMEA (1.9 ) 13.8 (55.8 ) (17.9 ) Segment income - APAC 35.8 31.5 57.4 59.5 Segment income - LaSalle 29.5 35.5 28.8 93.0 Less: Equity earnings (15.0 ) (17.1 ) (1.4 ) (32.3 ) Add: Restructuring and acquisition charges (33.5 ) (70.0 ) (75.8 ) (114.3 ) Operating income $ 154.9 171.6 $ 230.3 347.1

Business Combinations, Goodwi_2

Business Combinations, Goodwill and Other Intangible Assets (Tables)	9 Months Ended
	Sep. 30, 2020
Schedule of Business Acquisitions, Pro Forma Revenue [Line Items]
Summary of Earn-out Payments [Table Text Block]	Earn-Out Payments ($ in millions) September 30, 2020 December 31, 2019 Number of acquisitions with earn-out payments subject to the achievement of certain performance criteria 42 44 Maximum earn-out payments (undiscounted) $ 221.3 $ 268.9 Short-term earn-out liabilities (fair value) 1 77.0 53.9 Long-term earn-out liabilities (fair value) 1 18.0 94.5 1 Included in Short-term and Long-term acquisition-related obligations on the Condensed Consolidated Balance Sheets.
Movements in Goodwill by Reporting Segment	The following tables detail, by reporting segment, movements in goodwill. Real Estate Services (in millions) Americas EMEA Asia Pacific LaSalle Consolidated Balance as of December 31, 2019 $ 2,877.6 915.9 317.6 57.1 $ 4,168.2 Dispositions — (0.7 ) — — (0.7 ) Impact of exchange rate movements (1.1 ) (4.7 ) 2.6 (0.3 ) (3.5 ) Balance as of September 30, 2020 $ 2,876.5 910.5 320.2 56.8 $ 4,164.0 Real Estate Services (in millions) Americas EMEA Asia Pacific LaSalle Consolidated Balance as of December 31, 2018 $ 1,452.0 906.8 316.8 22.2 $ 2,697.8 Additions, net of adjustments 1,392.9 1.6 — 35.5 1,430.0 Dispositions — (0.9 ) — — (0.9 ) Impact of exchange rate movements 0.3 (37.6 ) (4.6 ) (1.8 ) (43.7 ) Balance as of September 30, 2019 $ 2,845.2 869.9 312.2 55.9 $ 4,083.2
Movements in Gross Carrying Amount and Accumulated Amortization of Finite-Lived Intangible Assets	The following tables detail, by reporting segment, movements in the gross carrying amount and accumulated amortization of our identifiable intangibles. MSRs Other Intangibles (in millions) Americas Americas EMEA Asia Pacific LaSalle Consolidated Gross Carrying Amount Balance as of December 31, 2019 $ 480.4 285.7 55.9 21.4 54.0 $ 897.4 Additions, net of adjustments (1) 77.9 — — 0.5 — 78.4 Adjustment for fully amortized intangibles (30.9 ) (14.1 ) (0.4 ) — — (45.4 ) Impact of exchange rate movements — (0.2 ) (1.5 ) 0.3 1.9 0.5 Balance as of September 30, 2020 $ 527.4 271.4 54.0 22.2 55.9 $ 930.9 Accumulated Amortization Balance as of December 31, 2019 $ (104.0 ) (68.3 ) (33.1 ) (6.7 ) (2.7 ) $ (214.8 ) Amortization, net (2) (65.5 ) (35.0 ) (5.2 ) (1.1 ) (2.0 ) (108.8 ) Adjustment for fully amortized intangibles 30.9 14.1 0.4 — — 45.4 Impact of exchange rate movements — 0.4 0.9 (0.1 ) — 1.2 Balance as of September 30, 2020 $ (138.6 ) (88.8 ) (37.0 ) (7.9 ) (4.7 ) $ (277.0 ) Net book value as of September 30, 2020 $ 388.8 182.6 17.0 14.3 51.2 $ 653.9 (1) Included in this amount for MSRs was (i) $15.3 million relating to prepayments/write-offs due to prepayments of the underlying obligation for which we assumed, acquired or retained the servicing rights and (ii) $1.9 million relating to a net impairment valuation allowance. (2) Amortization of MSRs is included in Revenue before reimbursements within the Condensed Consolidated Statements of Comprehensive Income. MSRs Other Intangibles (in millions) Americas Americas EMEA Asia Pacific LaSalle Consolidated Gross Carrying Amount Balance as of December 31, 2018 $ 266.2 90.0 83.1 23.5 43.9 $ 506.7 Additions, net of adjustments (1) 208.3 194.5 — — 10.3 413.1 Adjustment for fully amortized intangibles (21.8 ) (0.7 ) (22.1 ) (2.0 ) — (46.6 ) Impairments — (0.5 ) — — — (0.5 ) Impact of exchange rate movements — — (2.8 ) (0.8 ) (1.6 ) (5.2 ) Balance as of September 30, 2019 $ 452.7 283.3 58.2 20.7 52.6 $ 867.5 Accumulated Amortization Balance as of December 31, 2018 $ (72.4 ) (38.8 ) (51.8 ) (6.8 ) — $ (169.8 ) Amortization, net (2) (41.6 ) (18.9 ) (7.5 ) (1.6 ) (2.0 ) (71.6 ) Adjustment for fully amortized intangibles 21.8 0.7 22.1 2.0 — 46.6 Impairments — 0.5 — — — 0.5 Impact of exchange rate movements — — 2.2 0.2 — 2.4 Balance as of September 30, 2019 $ (92.2 ) (56.5 ) (35.0 ) (6.2 ) (2.0 ) $ (191.9 ) Net book value as of September 30, 2019 $ 360.5 226.8 23.2 14.5 50.6 $ 675.6 (1) Included in this amount for MSRs was $10.6 million relating to prepayments/write-offs due to prepayments of the underlying obligation for which we assumed, acquired or retained the servicing rights. (2) Amortization of MSRs is included in Revenue before reimbursements within the Condensed Consolidated Statements of Comprehensive Income.
Future Amortization Expense for Finite-Lived Intangible Assets	The remaining estimated future amortization expense of MSRs and other identifiable intangible assets, by year, as of September 30, 2020 , is presented in the following table. (in millions) MSRs Other Intangibles Total 2020 (remaining 3 months) $ 17.2 16.0 $ 33.2 2021 66.2 48.6 114.8 2022 59.3 42.9 102.2 2023 53.0 40.5 93.5 2024 45.4 36.2 81.6 2025 37.7 18.9 56.6 Thereafter 110.0 10.0 120.0 Total $ 388.8 213.1 $ 601.9

Investments in Real Estate Ve_2

Investments in Real Estate Ventures (Tables)	9 Months Ended
	Sep. 30, 2020
Equity Method Investments and Joint Ventures [Abstract]
Balance Sheet Amounts Consolidated for Variable Interest Entity [Table Text Block]	Summarized financial information for our consolidated VIEs is presented in the following tables. (in millions) September 30, 2020 December 31, 2019 Property and equipment, net $ 132.9 126.3 Investments in real estate ventures 9.2 13.2 Other assets 9.6 14.3 Total assets $ 151.7 153.8 Other current liabilities $ 2.6 3.2 Mortgage indebtedness (included in Other liabilities) 71.3 69.7 Total liabilities 73.9 72.9 Members' equity (included in Noncontrolling interest) 77.8 80.9 Total liabilities and members' equity $ 151.7 153.8
Comprehensive Income Amounts Consolidated for Variable Interest Entity [Table Text Block]	Three Months Ended September 30, Nine Months Ended September 30, (in millions) 2020 2019 2020 2019 Revenue $ 3.6 1.9 $ 10.8 4.9 Operating and other expenses (3.7 ) (2.1 ) (11.9 ) (5.3 ) Net gains on sale of investments 1 3.1 — 15.3 — Net income (loss) $ 3.0 (0.2 ) $ 14.2 (0.4 )
Investments in real estate ventures, Fair Value	The table below shows the movement in our investments in real estate ventures reported at fair value. (in millions) 2020 2019 Fair value investments as of January 1, $ 328.6 247.3 Investments 36.8 67.1 Distributions (58.8 ) (39.2 ) Change in fair value, net (9.1 ) 29.8 Foreign currency translation adjustments, net 1.5 (0.8 ) Fair value investments as of September 30, $ 299.0 304.2

Stock-based Compensation (Table

Stock-based Compensation (Tables)	9 Months Ended
	Sep. 30, 2020
Share-based Payment Arrangement [Abstract]
Restricted Stock Unit Activity	Restricted stock unit ("RSU") and performance stock unit ("PSU") awards activity is presented in the following tables. RSU Shares PSU Shares Total Shares Weighted Average Weighted Average Unvested as of June 30, 2020 1,343.2 558.8 1,902.0 $ 137.93 2.01 Granted 11.2 4.4 15.6 107.51 Vested (213.5 ) — (213.5 ) 140.38 Forfeited (13.0 ) (4.5 ) (17.5 ) 134.03 Unvested as of September 30, 2020 1,127.9 558.7 1,686.6 $ 137.49 1.85 Unvested as of June 30, 2019 436.7 259.6 696.3 $ 144.17 2.25 Granted 1,130.1 — 1,130.1 141.14 Vested (45.8 ) — (45.8 ) 122.48 Forfeited (8.1 ) — (8.1 ) 138.96 Unvested as of September 30, 2019 1,512.9 259.6 1,772.5 $ 142.82 2.59 RSU Shares PSU Shares Total Shares Weighted Average Weighted Average Remaining (in years) Unvested as of December 31, 2019 1,532.3 286.8 1,819.1 $ 141.51 2.39 Granted 173.1 276.4 449.5 114.19 Vested (548.4 ) — (548.4 ) 137.92 Forfeited (29.1 ) (4.5 ) (33.6 ) 136.96 Unvested as of September 30, 2020 1,127.9 558.7 1,686.6 $ 137.49 1.85 Unvested as of December 31, 2018 559.6 93.1 652.7 $ 131.32 2.02 Granted 1,243.4 166.9 1,410.3 149.22 Vested (268.3 ) — (268.3 ) 116.25 Forfeited (21.8 ) (0.4 ) (22.2 ) 134.54 Unvested as of September 30, 2019 1,512.9 259.6 1,772.5 $ 142.82 2.59

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2020
Fair Value Disclosures [Abstract]
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis	The following table categorizes by level in the fair value hierarchy the estimated fair value of our assets and liabilities measured at fair value on a recurring basis. September 30, 2020 December 31, 2019 (in millions) Level 1 Level 2 Level 3 Level 1 Level 2 Level 3 Assets Investments in real estate ventures - fair value $ 56.4 — 50.2 69.4 — 34.4 Foreign currency forward contracts receivable — 3.2 — — 10.5 — Warehouse receivables — 1,750.6 — — 527.1 — Deferred compensation plan assets — 410.7 — — 349.9 — Mortgage banking derivative assets — — 87.0 — — 36.1 Total assets at fair value $ 56.4 2,164.5 137.2 69.4 887.5 70.5 Liabilities Foreign currency forward contracts payable — 10.5 — — 4.4 — Deferred compensation plan liabilities — 388.4 — — 346.1 — Earn-out liabilities — — 95.0 — — 148.5 Mortgage banking derivative liabilities — — 80.8 — — 25.9 Total liabilities at fair value $ — 398.9 175.8 — 350.5 174.4
Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation	The tables below present a reconciliation for assets and liabilities measured at fair value on a recurring basis using significant unobservable inputs (Level 3). Balance as of June 30, 2020 Net change in fair value Foreign CTA 1 Purchases / Additions Settlements Balance as of September 30, 2020 Investments in real estate ventures $ 44.3 4.3 — 1.6 — $ 50.2 Mortgage banking derivative assets and liabilities, net (5.5 ) (2.6 ) — 48.2 (33.9 ) 6.2 Earn-out liabilities 97.8 (0.6 ) 0.7 — (2.9 ) 95.0 Balance as of June 30, 2019 Net change in fair value Foreign CTA 1 Purchases / Additions Settlements Balance as of September 30, 2019 Investments in real estate ventures $ 20.0 0.8 — 6.5 (0.8 ) $ 26.5 Mortgage banking derivative assets and liabilities, net (1.3 ) (7.1 ) — 45.3 (9.9 ) 27.0 Earn-out liabilities 180.3 0.7 (2.4 ) — (4.8 ) 173.8 (in millions) Balance as of December 31, 2019 Net change in fair value Foreign CTA 1 Purchases / Additions Settlements Balance as of September 30, 2020 Investments in real estate ventures $ 34.4 6.8 — 9.0 — $ 50.2 Mortgage banking derivative assets and liabilities, net 10.2 (93.2 ) — 112.9 (23.7 ) 6.2 Earn-out liabilities 148.5 (8.2 ) (0.2 ) — (45.1 ) 95.0 (in millions) Balance as of December 31, 2018 Net change in fair value Foreign CTA 1 Purchases / Additions Settlements Balance as of June 30, 2019 Investments in real estate ventures $ 11.5 0.8 — 15.0 (0.8 ) $ 26.5 Mortgage banking derivative assets and liabilities, net 6.3 (28.8 ) — 77.8 (28.3 ) 27.0 Earn-out liabilities 192.0 20.7 (2.6 ) 1.5 (37.8 ) 173.8 1 CTA: Currency translation adjustments
Fair Value, Qualitative Disclosures About Assets and Liabilities using Unobservable Inputs	Net change in fair value, included in the tables above, is reported in Net income as follows. Category of Assets/Liabilities using Unobservable Inputs Condensed Consolidated Statements of Comprehensive Income Account Caption Earn-out liabilities (Short-term and Long-term) Restructuring and acquisition charges Investments in real estate ventures Equity earnings Other current assets - Mortgage banking derivative assets Revenue before reimbursements Other current liabilities - Mortgage banking derivative liabilities Revenue before reimbursements

Debt Short-Term Borrowings and

Debt Short-Term Borrowings and Long-Term Debt (Tables)	9 Months Ended
	Sep. 30, 2020
Debt Disclosure [Abstract]
Schedule of Debt [Table Text Block]	Short-term borrowings and long-term debt obligations are composed of the following. (in millions) September 30, 2020 December 31, 2019 Short-term borrowings: Local overdraft facilities $ 12.2 44.8 Other short-term borrowings 94.2 75.3 Total short-term borrowings $ 106.4 120.1 Credit facility, net of debt issuance costs of $9.6 and $12.3 390.4 512.7 Long-term senior notes, 4.4%, face amount of $275.0, due November 2022, net of debt issuance costs of $0.8 and $1.2 274.2 273.8 Long-term senior notes, 1.96%, face amount of €175.0, due June 2027, net of debt issuance costs of $0.9 and $0.9 204.4 195.4 Long-term senior notes, 2.21%, face amount of €175.0, due June 2029, net of debt issuance costs of $1.0 and $1.0 204.3 195.4 Total debt $ 1,179.7 1,297.4
Schedule of Credit Facility, Average Outstanding Amount [Table Text Block]	The following tables provides additional information on our Facility. Three Months Ended September 30, Nine Months Ended September 30, ($ in millions) 2020 2019 2020 2019 Average outstanding borrowings under the Facility $ 758.9 1,408.5 $ 1,014.3 763.9 Effective interest rate on the Facility 1.1 % 3.1 % 1.6 % 3.2 %

Debt Warehouse Facilities (Tabl

Debt Warehouse Facilities (Tables)	9 Months Ended
	Sep. 30, 2020
Warehouse Facilities [Abstract]
Schedule of Warehouse Facilities	Warehouse Facilities September 30, 2020 December 31, 2019 ($ in millions) Outstanding Balance Maximum Capacity Outstanding Balance Maximum Capacity Warehouse Facilities: LIBOR plus 1.15%, October 21, 2020 1 $ 300.2 375.0 104.4 375.0 LIBOR plus 1.40%, expires September 18, 2021 2 1,016.0 1,200.0 184.8 775.0 LIBOR plus 1.40%, expires August 27, 2021 3 85.1 200.0 11.4 100.0 Fannie Mae ASAP 4 program, LIBOR plus 1.15% 84.3 n/a 53.6 n/a LIBOR plus 1.25% 5 239.2 500.0 151.6 1,000.0 LIBOR plus 1.25% — — 11.0 175.0 Gross warehouse facilities 1,724.8 2,275.0 516.8 2,425.0 Debt issuance costs (1.0 ) n/a (0.9 ) n/a Total warehouse facilities $ 1,723.8 2,275.0 515.9 2,425.0 1 In the third quarter of 2020, JLL extended the Warehouse facility; previously, the facility had a maturity date of September 21, 2020. In October 2020, JLL extended the Warehouse facility to September 20, 2021 with a maximum capacity of $400 million and an increase to the interest rate (to LIBOR plus 1.40%). 2 In the third quarter of 2020, JLL extended the Warehouse facility with an increase to the interest rate; previously, the facility had a maturity date of September 19, 2020 and an interest rate of LIBOR plus 1.15%. 3 In the third quarter of 2020, JLL extended the Warehouse facility with an increase to the interest rate; previously, the facility had a maturity date of August 31, 2020 and an interest rate of LIBOR plus 1.15%. 4 As Soon As Pooled ("ASAP") funding program 5 In the third quarter of 2020, the maximum capacity was reduced from $1.0 billion to $500 million.

Commitments and Contingencies (

Commitments and Contingencies (Tables)	9 Months Ended
	Sep. 30, 2020
Commitments and Contingencies Disclosure [Abstract]
Schedule of Loss Contingencies by Contingency [Table Text Block]	The following table shows the professional indemnity accrual activity and related payments. (in millions) December 31, 2019 $ 38.1 New claims 5.8 Prior year claims adjustments (including foreign currency changes) 0.8 Claims paid — September 30, 2020 $ 44.7 December 31, 2018 $ 43.1 New claims 0.1 Prior year claims adjustments (including foreign currency changes) (4.4 ) Claims paid (1.1 ) September 30, 2019 $ 37.7

Restructuring and Acquisition_2

Restructuring and Acquisition Charges Restructuring and Related Activities (Tables)	9 Months Ended
	Sep. 30, 2020
Restructuring Cost and Reserve [Line Items]
Restructuring Charges and Related Payment Activity	The following tables show the accrual activity and payments relating to cash-based Restructuring and acquisition charges. (in millions) Severance & Employment-Related Lease Exit Restructuring, Acquisition and Total December 31, 2019 $ 24.3 8.4 3.8 $ 36.5 Accruals 27.6 9.3 16.6 53.5 Payments made (22.1 ) (16.0 ) (20.4 ) (58.5 ) September 30, 2020 $ 29.8 1.7 — $ 31.5 (in millions) Severance & Employment-Related Lease Other Restructuring, Total December 31, 2018 $ 14.0 0.6 0.5 $ 15.1 Accruals 17.6 5.8 56.2 79.6 Payments made (21.2 ) (1.5 ) (54.8 ) (77.5 ) September 30, 2019 $ 10.4 4.9 1.9 $ 17.2
Restructuring, Impairment, and Other Activities Disclosure [Text Block]	Restructuring and acquisition charges are presented in table below. Three Months Ended September 30, Nine Months Ended September 30, (in millions) 2020 2019 2020 2019 Severance and other employment-related charges $ 19.3 7.2 $ 27.6 17.6 Restructuring, pre-acquisition and post-acquisition charges 8.6 48.1 25.9 62.0 Stock-based compensation expense for HFF retention awards 6.2 14.0 30.5 14.0 Fair value adjustments to earn-out liabilities (0.6 ) 0.7 (8.2 ) 20.7 Restructuring and acquisition charges $ 33.5 70.0 $ 75.8 114.3

Accumulated Other Comprehensi_2

Accumulated Other Comprehensive Income (Loss) by Component (Tables)	9 Months Ended
	Sep. 30, 2020
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block]	All other reclassifications relating to pension and postretirement benefits are reported within Other income. (in millions) Pension and postretirement benefit Cumulative foreign currency translation adjustment Total Balance as of June 30, 2020 $ (72.0 ) (465.4 ) $ (537.4 ) Other comprehensive income before reclassification — 59.3 59.3 Amounts reclassified from AOCI after tax expense of $ - , $ - and $ - 0.7 — 0.7 Other comprehensive income after tax expense of $ - , $ - and $ - 0.7 59.3 60.0 Balance as of September 30, 2020 $ (71.3 ) (406.1 ) $ (477.4 ) (in millions) Pension and postretirement benefit Cumulative foreign currency translation adjustment Total Balance as of June 30, 2019 $ (59.2 ) (390.8 ) $ (450.0 ) Other comprehensive loss before reclassification — (34.6 ) (34.6 ) Amounts reclassified from AOCI after tax expense of $ - , $ - and $ - 0.1 — 0.1 Other comprehensive loss after tax expense of $ - , $ - and $ - 0.1 (34.6 ) (34.5 ) Balance as of September 30, 2019 $ (59.1 ) (425.4 ) $ (484.5 ) (in millions) Pension and postretirement benefit Cumulative foreign currency translation adjustment Total Balance as of December 31, 2019 $ (72.0 ) (355.8 ) $ (427.8 ) Other comprehensive loss before reclassification — (50.3 ) (50.3 ) Amounts reclassified from AOCI after tax expense of $ - , $ - and $ - 0.7 — 0.7 Other comprehensive loss after tax expense of $ - , $ - and $ - 0.7 (50.3 ) (49.6 ) Balance as of September 30, 2020 $ (71.3 ) (406.1 ) $ (477.4 ) (in millions) Pension and postretirement benefit Cumulative foreign currency translation adjustment Total Balance as of December 31, 2018 $ (57.4 ) (398.8 ) $ (456.2 ) Other comprehensive income before reclassification — (26.6 ) (26.6 ) Amounts reclassified from AOCI after tax expense of $ - , $ - and $ - (1.7 ) — (1.7 ) Other comprehensive (loss) income after tax expense of $ - , $ - and $ - (1.7 ) (26.6 ) (28.3 ) Balance as of September 30, 2019 $ (59.1 ) (425.4 ) $ (484.5 )

New Accounting Standards Cumu_2

New Accounting Standards Cumulative impact upon adoption of ASC Topic 326 (Details) - USD ($) $ in Millions	Sep. 30, 2020	Jan. 01, 2020	Dec. 31, 2019
Adjustment due to adoption of ASC Topic 326 [Line Items]
Trade receivables, allowances	$ (81.3)	$ (71.7)	$ (68.1)
Deferred Income Tax Assets, Net	235.3	250.9	245.4
Contract with Customer, Asset, Allowance for Credit Loss	(3.2)	(1.7)	0
Loan loss guarantee reserve	45.7	15.1
Retained earnings	$ 3,725.9	3,573.4	$ 3,588.3
Accounting Standards Update 2016-13 [Member]
Adjustment due to adoption of ASC Topic 326 [Line Items]
Trade receivables, allowances		(3.6)
Deferred Income Tax Assets, Net		5.5
Contract with Customer, Asset, Allowance for Credit Loss		(1.7)
Loan loss guarantee reserve		15.1
Retained earnings		$ (14.9)

Revenue Recognition Revenue R_2

Revenue Recognition Revenue Recognition (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Disaggregation of Revenue [Line Items]
Contract with Customer, Asset, after Allowance for Credit Loss	$ 389.8		$ 389.8		$ 419.3
Contract with Customer, Liability	85.7		$ 85.7		$ 87.7
Percentage of Revenue, Remaining Performance Obligation			5.00%
Out of Scope of Topic 606 Revenue [Member]
Disaggregation of Revenue [Line Items]
Fees and Commissions, Mortgage Banking and Servicing	$ 72	$ 74.3	$ 174.7	$ 137.6

Revenue Recognition Contract As

Revenue Recognition Contract Assets & Liabilities (Details) - USD ($) $ in Millions	Sep. 30, 2020	Jan. 01, 2020	Dec. 31, 2019
Disaggregation of Revenue [Line Items]
Contract with Customer, Asset, after Allowance for Credit Loss	$ 389.8		$ 419.3
Contract with Customer, Asset, Allowance for Credit Loss	(3.2)	$ (1.7)	0
Contract with Customer, Asset, before Allowance for Credit Loss	386.6		419.3
Contract with Customer, Liability	$ 85.7		$ 87.7

Business Segments (Details)

Business Segments (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Segment revenue:
Revenue Before Reimbursements	$ 2,091.4	$ 2,545.8	$ 6,152.9	$ 6,855.6
Revenue	3,978.1	4,495.6	11,744.5	12,582.7
Operating expenses:
Depreciation and amortization	54.9	53.6	166.8	145.6
Equity in earnings (losses)	(15)	(17.1)	(1.4)	(32.3)
Cost of Reimbursable Expenses	1,886.7	1,949.8	5,591.6	5,727.1
Revenue	3,978.1	4,495.6	11,744.5	12,582.7
Operating Income (Loss)	154.9	171.6	230.3	347.1
Restructuring and acquisition charges	(33.5)	(70)	(75.8)	(114.3)
Reportable Subsegments [Member] | Americas [Member]
Segment revenue:
Revenue	2,380.8	2,687.6	7,132.9	7,401.3
Operating expenses:
Depreciation and amortization	36.4	35.3	112.9	88.9
Equity in earnings (losses)	(4.8)	(1.5)	(20.4)	(1.6)
Operating Income (Loss), Including Income (Loss) from Equity Method Investments	140	177.9	277.1	359.1
Revenue	2,380.8	2,687.6	7,132.9	7,401.3
Reportable Subsegments [Member] | EMEA [Member]
Segment revenue:
Revenue	743.8	862.6	2,125.9	2,404.3
Operating expenses:
Depreciation and amortization	9.8	10.1	28	32.7
Equity in earnings (losses)	(0.8)	0	(0.8)	1
Operating Income (Loss), Including Income (Loss) from Equity Method Investments	(1.9)	13.8	(55.8)	(17.9)
Revenue	743.8	862.6	2,125.9	2,404.3
Reportable Subsegments [Member] | Asia Pacific [Member]
Segment revenue:
Revenue	743.2	833.8	2,170.6	2,437.7
Operating expenses:
Depreciation and amortization	6.9	6.5	20.5	19.3
Equity in earnings (losses)	(0.9)	(0.7)	(0.7)	(1.4)
Operating Income (Loss), Including Income (Loss) from Equity Method Investments	35.8	31.5	57.4	59.5
Revenue	743.2	833.8	2,170.6	2,437.7
Investment Management [Member]
Segment revenue:
Revenue	110.3	111.6	315.1	339.4
Operating expenses:
Depreciation and amortization	1.8	1.7	5.4	4.7
Equity in earnings (losses)	(8.5)	(14.9)	20.5	(30.3)
Operating Income (Loss), Including Income (Loss) from Equity Method Investments	29.5	35.5	28.8	93
Revenue	110.3	111.6	315.1	339.4
Leasing [Member] | Reportable Subsegments [Member] | Americas [Member]
Segment revenue:
Revenue	325.2	472.7	1,022.2	1,354.3
Operating expenses:
Revenue	325.2	472.7	1,022.2	1,354.3
Leasing [Member] | Reportable Subsegments [Member] | EMEA [Member]
Segment revenue:
Revenue	58.5	72.2	153.3	190.3
Operating expenses:
Revenue	58.5	72.2	153.3	190.3
Leasing [Member] | Reportable Subsegments [Member] | Asia Pacific [Member]
Segment revenue:
Revenue	46.6	59.4	105.8	161.5
Operating expenses:
Revenue	46.6	59.4	105.8	161.5
Capital Markets [Member] | Reportable Subsegments [Member] | Americas [Member]
Segment revenue:
Revenue	190.8	323.2	579	553.1
Operating expenses:
Revenue	190.8	323.2	579	553.1
Capital Markets [Member] | Reportable Subsegments [Member] | EMEA [Member]
Segment revenue:
Revenue	73.3	106.2	196.5	248.7
Operating expenses:
Revenue	73.3	106.2	196.5	248.7
Capital Markets [Member] | Reportable Subsegments [Member] | Asia Pacific [Member]
Segment revenue:
Revenue	20.4	50.6	66.1	128.2
Operating expenses:
Revenue	20.4	50.6	66.1	128.2
Property & Facility Management [Member] | Reportable Subsegments [Member] | Americas [Member]
Segment revenue:
Revenue	1,433.3	1,386.3	4,331.6	4,119.2
Operating expenses:
Revenue	1,433.3	1,386.3	4,331.6	4,119.2
Property & Facility Management [Member] | Reportable Subsegments [Member] | EMEA [Member]
Segment revenue:
Revenue	348.7	387.1	1,044.2	1,137
Operating expenses:
Revenue	348.7	387.1	1,044.2	1,137
Property & Facility Management [Member] | Reportable Subsegments [Member] | Asia Pacific [Member]
Segment revenue:
Revenue	521.3	539.4	1,568.5	1,630.6
Operating expenses:
Revenue	521.3	539.4	1,568.5	1,630.6
Project & Development Services [Member] | Reportable Subsegments [Member] | Americas [Member]
Segment revenue:
Revenue	336.2	406	917.9	1,091.5
Operating expenses:
Revenue	336.2	406	917.9	1,091.5
Project & Development Services [Member] | Reportable Subsegments [Member] | EMEA [Member]
Segment revenue:
Revenue	190.8	234.2	558.3	633.9
Operating expenses:
Revenue	190.8	234.2	558.3	633.9
Project & Development Services [Member] | Reportable Subsegments [Member] | Asia Pacific [Member]
Segment revenue:
Revenue	104.5	145.7	296.5	393.9
Operating expenses:
Revenue	104.5	145.7	296.5	393.9
Advisory, Consulting and Other [Member] | Reportable Subsegments [Member] | Americas [Member]
Segment revenue:
Revenue	95.3	99.4	282.2	283.2
Operating expenses:
Revenue	95.3	99.4	282.2	283.2
Advisory, Consulting and Other [Member] | Reportable Subsegments [Member] | EMEA [Member]
Segment revenue:
Revenue	72.5	62.9	173.6	194.4
Operating expenses:
Revenue	72.5	62.9	173.6	194.4
Advisory, Consulting and Other [Member] | Reportable Subsegments [Member] | Asia Pacific [Member]
Segment revenue:
Revenue	50.4	38.7	133.7	123.5
Operating expenses:
Revenue	50.4	38.7	133.7	123.5
Advisory Fees [Member] | Investment Management [Member]
Segment revenue:
Revenue	84.6	79.9	251.1	237
Operating expenses:
Revenue	84.6	79.9	251.1	237
Transaction Fees & Other [Member] | Investment Management [Member]
Segment revenue:
Revenue	17.7	14.2	36.1	43.7
Operating expenses:
Revenue	17.7	14.2	36.1	43.7
Incentive Fees [Member] | Investment Management [Member]
Segment revenue:
Revenue	8	17.5	27.9	58.7
Operating expenses:
Revenue	$ 8	$ 17.5	$ 27.9	$ 58.7

Business Combinations (Details)

Business Combinations (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019	Dec. 31, 2018
Business Acquisition [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 85.9		$ 85.9
Business Combinations, Guaranteed Deferred Acquisition Obligation			0	$ 6.5
Business Combination, contingent earn-out consideration			0	842.7
Redeemable Noncontrolling Interest	7.9		$ 7.9		$ 8.6
Document Period End Date			Sep. 30, 2020
Payment for Contingent Consideration Liability, Total			$ 58.5
Goodwill	4,164	$ 4,083.2	4,164	4,083.2	4,168.2	$ 2,697.8
Reportable Subsegments [Member] | Americas [Member]
Business Acquisition [Line Items]
Goodwill	2,876.5	2,845.2	2,876.5	2,845.2	2,877.6	1,452
Reportable Subsegments [Member] | EMEA [Member]
Business Acquisition [Line Items]
Goodwill	910.5	869.9	910.5	869.9	915.9	906.8
Reportable Subsegments [Member] | Asia Pacific [Member]
Business Acquisition [Line Items]
Goodwill	320.2	312.2	320.2	312.2	317.6	316.8
Investment Management [Member]
Business Acquisition [Line Items]
Goodwill	56.8	55.9	56.8	55.9	$ 57.1	$ 22.2
HFF Acquisition [Member]
Business Acquisition [Line Items]
Business Combination, Integration Related Costs	$ 13.8	$ 60.1	$ 55.2	$ 69.8

Business Combinations, Goodwi_3

Business Combinations, Goodwill and Other Intangible Assets Business Combinations, Earn-out Payments (Details) $ in Millions	Sep. 30, 2020USD ($)acquisition	Dec. 31, 2019USD ($)acquisition
Summary of Earn-out Payments [Line Items]
Number Of Acquisitions Subject To Potential Earn Out Payments Provisions | acquisition	42	44
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High	$ 221.3	$ 268.9
Business Combination, Contingent Consideration, Liability, Current	92.6	74.4
Business Combination, Contingent Consideration, Liability, Noncurrent	39.6	124.1
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Summary of Earn-out Payments [Line Items]
Business Combination, Contingent Consideration, Liability, Current	77	53.9
Business Combination, Contingent Consideration, Liability, Noncurrent	$ 18	$ 94.5

Business Combinations, Goodwi_4

Business Combinations, Goodwill by Segment (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
BUSINESS COMBINATIONS, GOODWILL AND OTHER INTANGIBLE ASSETS [Abstract]
Finite-Lived Intangible Assets, Net	$ 601.9
Identifiable intangibles with indefinite useful lives	52
Goodwill [Line Items]
Servicing Asset at Amortized Cost, Other than Temporary Impairments	15.3	$ 10.6
Goodwill [Roll Forward]
Goodwill Additions, net of adjustments		1,430
Goodwill, Written off Related to Sale of Business Unit	(0.7)	(0.9)
Goodwill, Translation Adjustments	(3.5)	(43.7)
Goodwill	4,164	4,083.2
Goodwill	4,168.2	2,697.8
Asia Pacific [Member]
Goodwill [Roll Forward]
Goodwill, Written off Related to Sale of Business Unit	0	0
EMEA [Member]
Goodwill [Roll Forward]
Goodwill, Written off Related to Sale of Business Unit	(0.7)	(0.9)
Investment Management [Member]
Goodwill [Roll Forward]
Goodwill Additions, net of adjustments		35.5
Goodwill, Written off Related to Sale of Business Unit	0	0
Goodwill, Translation Adjustments	(0.3)	(1.8)
Goodwill	56.8	55.9
Goodwill	57.1	22.2
Americas [Member]
Goodwill [Roll Forward]
Goodwill, Written off Related to Sale of Business Unit	0	0
Americas [Member] | Reportable Subsegments [Member]
Goodwill [Roll Forward]
Goodwill Additions, net of adjustments		1,392.9
Goodwill, Translation Adjustments	(1.1)	0.3
Goodwill	2,876.5	2,845.2
Goodwill	2,877.6	1,452
EMEA [Member] | Reportable Subsegments [Member]
Goodwill [Roll Forward]
Goodwill Additions, net of adjustments		1.6
Goodwill, Translation Adjustments	(4.7)	(37.6)
Goodwill	910.5	869.9
Goodwill	915.9	906.8
Asia Pacific [Member] | Reportable Subsegments [Member]
Goodwill [Roll Forward]
Goodwill Additions, net of adjustments		0
Goodwill, Translation Adjustments	2.6	(4.6)
Goodwill	320.2	312.2
Goodwill	317.6	$ 316.8
Other Intangible Assets [Member]
BUSINESS COMBINATIONS, GOODWILL AND OTHER INTANGIBLE ASSETS [Abstract]
Finite-Lived Intangible Assets, Net	213.1
Mortgage servicing rights [Member]
BUSINESS COMBINATIONS, GOODWILL AND OTHER INTANGIBLE ASSETS [Abstract]
Finite-Lived Intangible Assets, Net	$ 388.8

Business Combinations Other Int

Business Combinations Other Intangibles by Segment (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019	Dec. 31, 2018
Schedule of Finite and Indefinite lived Intangible Assets by Segment [Line Items]
Document Period End Date	Sep. 30, 2020
Finite and Indefinite lived Intangible Assets, Additions	$ 78.4	$ 413.1
Adjustment for fully amortized intangibles	45.4	46.6
Impairment of Intangible Assets (Excluding Goodwill)		(0.5)
Finite And Indefinite Lived Intangible Assets Translation Adjustments	0.5	5.2
Intangible Assets, Gross (Excluding Goodwill)	930.9	867.5	$ 897.4	$ 506.7
Identified intangibles, with finite useful lives, accumulated amortization	(277)	(191.9)	(214.8)	(169.8)
Amortization expense	(108.8)	(71.6)
Accumulated Amortization Adjustment for fully Amortized Intangibles	(45.4)	(46.6)
Accelerated Depreciation on Intangibles		0.5
Net book value as of end of period	653.9	675.6	682.6
Servicing Asset at Amortized Cost, Other than Temporary Impairments	15.3	10.6
Impact of exchange rate movements	1.2	(2.4)
Valuation Allowance for Impairment of Recognized Servicing Assets, Deductions for Aggregate Write-Downs	1.9
Finite-Lived Intangible Assets, Amortization Expense, Maturity Schedule [Abstract]
2020 (3 months)	33.2
2021	114.8
2022	102.2
2023	93.5
2024	81.6
2025	56.6
Thereafter	120
Total	601.9
Mortgage servicing rights [Member]
Finite-Lived Intangible Assets, Amortization Expense, Maturity Schedule [Abstract]
2020 (3 months)	17.2
2021	66.2
2022	59.3
2023	53
2024	45.4
2025	37.7
Thereafter	110
Total	388.8
Mortgage servicing rights [Member] | Reportable Subsegments [Member] | Americas [Member]
Schedule of Finite and Indefinite lived Intangible Assets by Segment [Line Items]
Finite And Indefinite Lived Intangible Assets Gross			480.4
Finite and Indefinite lived Intangible Assets, Additions	77.9	208.3
Adjustment for fully amortized intangibles	30.9	21.8
Impairment of Intangible Assets (Excluding Goodwill)		0
Finite And Indefinite Lived Intangible Assets Translation Adjustments	0	0
Intangible Assets, Gross (Excluding Goodwill)	527.4	452.7		266.2
Identified intangibles, with finite useful lives, accumulated amortization	(138.6)	(92.2)	(104)	(72.4)
Amortization expense	(65.5)	(41.6)
Accumulated Amortization Adjustment for fully Amortized Intangibles	(30.9)	(21.8)
Accelerated Depreciation on Intangibles		0
Net book value as of end of period	388.8	360.5
Impact of exchange rate movements	0	0
Other Intangible Assets [Member]
Finite-Lived Intangible Assets, Amortization Expense, Maturity Schedule [Abstract]
2020 (3 months)	16
2021	48.6
2022	42.9
2023	40.5
2024	36.2
2025	18.9
Thereafter	10
Total	213.1
Other Intangible Assets [Member] | Reportable Subsegments [Member] | Americas [Member]
Schedule of Finite and Indefinite lived Intangible Assets by Segment [Line Items]
Finite and Indefinite lived Intangible Assets, Additions	0	194.5
Adjustment for fully amortized intangibles	14.1	0.7
Impairment of Intangible Assets (Excluding Goodwill)		(0.5)
Finite And Indefinite Lived Intangible Assets Translation Adjustments	(0.2)	0
Intangible Assets, Gross (Excluding Goodwill)	271.4	283.3	285.7	90
Identified intangibles, with finite useful lives, accumulated amortization	(88.8)	(56.5)	(68.3)	(38.8)
Amortization expense	(35)	(18.9)
Accumulated Amortization Adjustment for fully Amortized Intangibles	(14.1)	(0.7)
Accelerated Depreciation on Intangibles		0.5
Net book value as of end of period	182.6	226.8
Impact of exchange rate movements	0.4	0
Other Intangible Assets [Member] | Reportable Subsegments [Member] | EMEA [Member]
Schedule of Finite and Indefinite lived Intangible Assets by Segment [Line Items]
Finite and Indefinite lived Intangible Assets, Additions	0	0
Adjustment for fully amortized intangibles	0.4	22.1
Impairment of Intangible Assets (Excluding Goodwill)		0
Finite And Indefinite Lived Intangible Assets Translation Adjustments	(1.5)	2.8
Intangible Assets, Gross (Excluding Goodwill)	54	58.2	55.9	83.1
Identified intangibles, with finite useful lives, accumulated amortization	(37)	(35)	(33.1)	(51.8)
Amortization expense	(5.2)	(7.5)
Accumulated Amortization Adjustment for fully Amortized Intangibles	(0.4)	(22.1)
Accelerated Depreciation on Intangibles		0
Net book value as of end of period	17	23.2
Impact of exchange rate movements	0.9	(2.2)
Other Intangible Assets [Member] | Reportable Subsegments [Member] | Asia Pacific [Member]
Schedule of Finite and Indefinite lived Intangible Assets by Segment [Line Items]
Finite and Indefinite lived Intangible Assets, Additions	0.5	0
Adjustment for fully amortized intangibles	0	2
Impairment of Intangible Assets (Excluding Goodwill)		0
Finite And Indefinite Lived Intangible Assets Translation Adjustments	0.3	0.8
Intangible Assets, Gross (Excluding Goodwill)	22.2	20.7	21.4	23.5
Identified intangibles, with finite useful lives, accumulated amortization	(7.9)	(6.2)	(6.7)	(6.8)
Amortization expense	(1.1)	(1.6)
Accumulated Amortization Adjustment for fully Amortized Intangibles	0	(2)
Accelerated Depreciation on Intangibles		0
Net book value as of end of period	14.3	14.5
Impact of exchange rate movements	(0.1)	(0.2)
Other Intangible Assets [Member] | Investment Management [Member]
Schedule of Finite and Indefinite lived Intangible Assets by Segment [Line Items]
Finite and Indefinite lived Intangible Assets, Additions	0	10.3
Adjustment for fully amortized intangibles	0	0
Impairment of Intangible Assets (Excluding Goodwill)		0
Finite And Indefinite Lived Intangible Assets Translation Adjustments	1.9	1.6
Intangible Assets, Gross (Excluding Goodwill)	55.9	52.6	54	43.9
Identified intangibles, with finite useful lives, accumulated amortization	(4.7)	(2)	$ (2.7)	$ 0
Amortization expense	(2)	(2)
Accumulated Amortization Adjustment for fully Amortized Intangibles	0	0
Accelerated Depreciation on Intangibles		0
Net book value as of end of period	51.2	50.6
Impact of exchange rate movements	$ 0	$ 0

Investments in Real Estate Ve_3

Investments in Real Estate Ventures (Details) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020USD ($)investment	Sep. 30, 2019USD ($)	Sep. 30, 2020USD ($)investment	Sep. 30, 2019USD ($)	Dec. 31, 2019USD ($)
Schedule of Equity Method Investments [Line Items]
Document Period End Date			Sep. 30, 2020
Number of separate property or fund co-investments | investment	48		48
Property, Plant and Equipment, Net, consolidated VIE	$ 675.4		$ 675.4		$ 701.9
Investments in real estate ventures	389.6		389.6		404.2
Total assets	13,902.1		13,902.1		13,672.6
Other Liabilities, Current	313.6		313.6		203.2
Total liabilities	8,608		8,608		8,459.3
Total liabilities and equity	13,902.1		13,902.1		13,672.6
Revenue	3,978.1	$ 4,495.6	11,744.5	$ 12,582.7
Net income	134.6	129.3	166.5	261.8
Fair Value [Abstract]
Fair value investments at beginning of the period			328.6	247.3
Investments in Real Estate Ventures, at Fair Value, Additions			36.8	67.1
Investments in Real Estate Ventures, at Fair Value, Distributions			58.8	39.2
Unrealized Gain (Loss) on Investments			(9.1)	29.8
Investments in Real Estate Ventures, at Fair Value, Foreign Currency Translation			1.5	(0.8)
Fair value investments at end of the period	$ 299	304.2	$ 299	304.2
LaSalle Investment Company II [Member]
Schedule of Equity Method Investments [Line Items]
Partnership ownership interest (in hundredths)	48.78%		48.78%
Guarantor Obligations, Maximum Exposure, Undiscounted	$ 60.4		$ 60.4
Exclusive of LaSalle Investment Company II [Member]
Schedule of Equity Method Investments [Line Items]
Guarantor Obligations, Maximum Exposure, Undiscounted	338.8		338.8
Consolidated Variable Interest Entities [Member]
Schedule of Equity Method Investments [Line Items]
Property, Plant and Equipment, Net, consolidated VIE	132.9		132.9		126.3
Investments in real estate ventures	9.2		9.2		13.2
Other Assets, consolidated VIE	9.6		9.6		14.3
Total assets	151.7		151.7		153.8
Other Liabilities, Current	2.6		2.6		3.2
Loans Payable, Fair Value Disclosure, consolidated VIE	71.3		71.3		69.7
Total liabilities	73.9		73.9		72.9
Members' Equity, consolidated VIE	77.8		77.8		80.9
Total liabilities and equity	151.7		151.7		$ 153.8
Revenue	3.6	1.9	10.8	4.9
Other Expenses, consolidated VIE	(3.7)	(2.1)	(11.9)	(5.3)
Gains (Losses) on Sales of Investment Real Estate, consolidated VIE	3.1	0	15.3	0
Net income	$ 3	$ (0.2)	$ 14.2	$ (0.4)

Stock-based Compensation (Detai

Stock-based Compensation (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019	Dec. 31, 2018
Share-based Payment activity, additional disclosures [Abstract]
Document Period End Date					Sep. 30, 2020
Restricted Stock Units (RSUs)
Share-based Payment activity [Roll Forward]
Unvested at beginning of period (in shares)	1,343,200	436,700	1,532,300	559,600	1,532,300	559,600	559,600
Granted (in shares)	11,200	1,130,100			173,100	1,243,400
Vested (in shares)	(213,500)	(45,800)			(548,400)	(268,300)
Forfeited (in shares)	(13,000)	(8,100)			(29,100)	(21,800)
Unvested at end of period (in shares)	1,127,900	1,512,900	1,343,200	436,700	1,127,900	1,512,900	1,532,300	559,600
Performance Shares [Member]
Share-based Payment activity [Roll Forward]
Unvested at beginning of period (in shares)	558,800	259,600	286,800	93,100	286,800	93,100	93,100
Granted (in shares)	4,400	0			276,400	166,900
Vested (in shares)	0	0			0	0
Forfeited (in shares)	(4,500)	0			(4,500)	(400)
Unvested at end of period (in shares)	558,700	259,600	558,800	259,600	558,700	259,600	286,800	93,100
Share-based Payment Arrangement [Member]
Share-based Payment activity [Roll Forward]
Unvested at beginning of period (in shares)	1,902,000	696,300	1,819,100	652,700	1,819,100	652,700	652,700
Granted (in shares)	15,600	1,130,100			449,500	1,410,300
Vested (in shares)	(213,500)	(45,800)			(548,400)	(268,300)
Forfeited (in shares)	(17,500)	(8,100)			(33,600)	(22,200)
Unvested at end of period (in shares)	1,686,600	1,772,500	1,902,000	696,300	1,686,600	1,772,500	1,819,100	652,700
Share-based Payment activity, additional disclosures [Abstract]
Weighted average grant date fair value, beginning of period (in dollars per share)	$ 137.93	$ 144.17	$ 141.51	$ 131.32	$ 141.51	$ 131.32	$ 131.32
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	107.51	141.14			114.19	149.22
Weighted average grant date fair value, vested (in dollars per share)	140.38	122.48			137.92	116.25
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value	134.03	138.96			136.96	134.54
Weighted average grant date fair value, end of period (in dollars per share)	$ 137.49	$ 142.82	$ 137.93	$ 144.17	$ 137.49	$ 142.82	$ 141.51	$ 131.32
Weighted average remaining contractual life, unvested shares outstanding			2 years 3 days	2 years 3 months	1 year 10 months 6 days	2 years 7 months 2 days	2 years 4 months 20 days	2 years 7 days
Unamortized deferred compensation cost	$ 84.3				$ 84.3
HFF Acquisition [Member] | Share-based Payment Arrangement [Member]
Share-based Payment activity, additional disclosures [Abstract]
Unamortized deferred compensation cost	$ 41.5				$ 41.5

Fair Value Measurements (Detail

Fair Value Measurements (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2020	Dec. 31, 2019	Sep. 30, 2019	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Document Period End Date	Sep. 30, 2020
Derivative, Notional Amount	$ 2,030	$ 2,300
Fair value of long-term debt	686.1	685.9
Long-term debt, net of debt issuance costs	682.9	664.6
Investments, Fair Value Disclosure	299	328.6	$ 304.2	$ 247.3
Foreign currency forward contracts, net notional value	1,050	1,050
Deferred compensation plan, contra-equity, shares held in trust	5.6	5.7
Foreign Exchange Contract [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset, Fair Value, Gross Asset	3.4	10.6
Derivative Asset, Fair Value, Gross Liability	0.2	0.1
Derivative Liability, Fair Value, Gross Asset	1.9	0.8
Derivative Liability, Fair Value, Gross Liability	12.4	5.2
Long-Term Senior Notes [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Unamortized Debt Issuance Expense	2.7	3.1
Fair Value, Recurring [Member] | Fair Value Measured at Net Asset Value Per Share [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	192.4	224.8
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	0	0
Foreign currency forward contract, current asset amount	3.2	10.5
Foreign currency forward contract, current liability amount	10.5	4.4
Deferred compensation plan assets	410.7	349.9
Deferred compensation plan liabilities	$ 388.4	$ 346.1

Fair Value Measurements (Assets

Fair Value Measurements (Assets and Liabilities Measured on a Recurring Basis) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Jun. 30, 2020	Dec. 31, 2019	Jun. 30, 2019	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	$ 299	$ 304.2	$ 299	$ 304.2		$ 328.6		$ 247.3
Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	56.4		56.4			69.4
Foreign currency forward contracts receivable	0		0			0
Loans Receivable, Fair Value Disclosure	0		0			0
Deferred compensation plan assets	0		0			0
Mortgage banking derivative asset	0		0			0
Total assets at fair value	56.4		56.4			69.4
Foreign currency forward contracts payable	0		0			0
Deferred compensation plan liabilities	0		0			0
Business Combination, Contingent Consideration, Liability	0		0			0
Mortgage banking derivative liabilities	0		0			0
Total liabilities at fair value	0		0			0
Fair Value, Inputs, Level 2 [Member] | Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	0		0			0
Foreign currency forward contracts receivable	3.2		3.2			10.5
Loans Receivable, Fair Value Disclosure	1,750.6		1,750.6			527.1
Deferred compensation plan assets	410.7		410.7			349.9
Mortgage banking derivative asset	0		0			0
Total assets at fair value	2,164.5		2,164.5			887.5
Foreign currency forward contracts payable	10.5		10.5			4.4
Deferred compensation plan liabilities	388.4		388.4			346.1
Business Combination, Contingent Consideration, Liability	0		0			0
Mortgage banking derivative liabilities	0		0			0
Total liabilities at fair value	398.9		398.9			350.5
Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net	6.2	27	6.2	27	$ (5.5)	10.2	$ (1.3)	6.3
Investments, Fair Value Disclosure	50.2	26.5	50.2	26.5	44.3	34.4	20	11.5
Foreign currency forward contracts receivable	0		0			0
Loans Receivable, Fair Value Disclosure	0		0			0
Deferred compensation plan assets	0		0			0
Mortgage banking derivative asset	87		87			36.1
Total assets at fair value	137.2		137.2			70.5
Foreign currency forward contracts payable	0		0			0
Deferred compensation plan liabilities	0		0			0
Business Combination, Contingent Consideration, Liability	95	173.8	95	173.8	$ 97.8	148.5	$ 180.3	$ 192
Mortgage banking derivative liabilities	80.8		80.8			25.9
Total liabilities at fair value	175.8		175.8			$ 174.4
Investments [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	4.3	0.8	6.8	0.8
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)	0	0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	1.6	6.5	9	15
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	$ 0	$ 0.8	$ 0	$ 0.8

Fair Value Measurements Fair Va

Fair Value Measurements Fair Value Measurements (Reconciliation of Assets and Liabilities Measured at Fair Value on a Recurring Basis Using Significant Unobservable Inputs) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Jun. 30, 2020	Dec. 31, 2019	Jun. 30, 2019	Dec. 31, 2018
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Investments, Fair Value Disclosure	$ 299	$ 304.2	$ 299	$ 304.2		$ 328.6		$ 247.3
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Investments, Fair Value Disclosure	50.2	26.5	50.2	26.5	$ 44.3	$ 34.4	$ 20	$ 11.5
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Business Combination, Contingent Consideration, Liability, Beginning Balance	97.8	180.3	148.5	192
Derivative Assets (Liabilities), at Fair Value, Net, Beginning Balance	(5.5)	(1.3)	10.2	6.3
Business Combination, Contingent Consideration, Liability, Ending Balance	95	173.8	95	173.8
Derivative Assets (Liabilities), at Fair Value, Net, Ending Balance	6.2	27	6.2	27
Earn-out Liabilities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	(0.6)	0.7	(8.2)	20.7
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)	0.7	(2.4)	(0.2)	(2.6)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0	0	0	1.5
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	(2.9)	(4.8)	(45.1)	(37.8)
Derivative [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	(2.6)	(7.1)	(93.2)	(28.8)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)	0	0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	48.2	45.3	112.9	77.8
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	(33.9)	(9.9)	(23.7)	(28.3)
Investments [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	4.3	0.8	6.8	0.8
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)	0	0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	1.6	6.5	9	15
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	$ 0	$ (0.8)	$ 0	$ (0.8)

Debt Short-Term Borrowings an_2

Debt Short-Term Borrowings and Long-Term Debt (Details) - USD ($)	9 Months Ended
	Sep. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Document Period End Date	Sep. 30, 2020
Bank Overdrafts	$ 12,200,000	$ 44,800,000
Other Short-term Borrowings	94,200,000	75,300,000
Short-term Debt	106,400,000	120,100,000
Long-term debt, net of debt issuance costs	682,900,000	664,600,000
Debt, Long-term and Short-term, Combined Amount	1,179,700,000	1,297,400,000
Line of Credit [Member]
Debt Instrument [Line Items]
Unamortized Debt Issuance Expense	9,600,000	12,300,000
Long-term senior notes, 4.4%, due November 2022 [Member]
Debt Instrument [Line Items]
Long-term debt, net of debt issuance costs	274,200,000	273,800,000
Debt Instrument, Face Amount	$ 275,000,000	$ 275,000,000
Debt Instrument, Interest Rate, Stated Percentage	4.40%	4.40%
Unamortized Debt Issuance Expense	$ 0.8	$ 1.2
Long-term senior notes, Euro notes, 1.96%, due June 2027 [Member]
Debt Instrument [Line Items]
Long-term debt, net of debt issuance costs	204,400,000	195,400,000
Debt Instrument, Face Amount	$ 175,000,000	$ 175,000,000
Debt Instrument, Interest Rate, Stated Percentage	1.96%	1.96%
Unamortized Debt Issuance Expense	$ 0.9	$ 0.9
Long-term senior notes, Euro notes, 2.21%, due June 2029 [Member]
Debt Instrument [Line Items]
Long-term debt, net of debt issuance costs	204,300,000	195,400,000
Debt Instrument, Face Amount	$ 175,000,000	$ 175,000,000
Debt Instrument, Interest Rate, Stated Percentage	2.21%	2.21%
Unamortized Debt Issuance Expense	$ 1	$ 1

Credit Facility (Details)

Credit Facility (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Line of Credit Facility [Line Items]
Long-term Line of Credit, Noncurrent, Net of Debt Issuance Costs	$ 390.4		$ 390.4		$ 512.7
Line of Credit Facility, Maximum Borrowing Capacity	85.9		85.9
Letters of Credit Outstanding, Amount	0.7		0.7		0.8
Line of Credit [Member]
Line of Credit Facility [Line Items]
Unamortized Debt Issuance Expense	9.6		9.6		12.3
Long-term Line of Credit, Noncurrent, Net of Debt Issuance Costs	390.4		390.4		$ 512.7
Line of Credit Facility, Maximum Borrowing Capacity	2,750		2,750
Line of Credit Facility, Average Outstanding Amount	$ 758.9	$ 1,408.5	$ 1,014.3	$ 763.9
Pricing on the Facility based on market rates			LIBOR plus 0.875% to 1.35%
Description of Variable Rate Basis			LIBOR
Basis spread on variable rate (in hundredths)			0.95%
Line of Credit Facility, Interest Rate During Period	1.10%	3.10%	1.60%	3.20%

Debt Warehouse Facilities (Deta

Debt Warehouse Facilities (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2020	Dec. 31, 2019
Line of Credit Facility [Line Items]
Document Period End Date	Sep. 30, 2020
Line of Credit Facility, Maximum Borrowing Capacity	$ 85.9
Warehouse facilities	1,723.8	$ 515.9
Warehouse Agreement Borrowings [Member]
Line of Credit Facility [Line Items]
Unamortized Debt Issuance Expense	1	0.9
Agreement expires September 21, 2020, Extension [Member] [Member]
Line of Credit Facility [Line Items]
Line of Credit, Current	300.2	104.4
Line of Credit Facility, Maximum Borrowing Capacity	$ 375	375
Pricing on the Facility based on market rates	LIBOR plus 1.15%
Huntington Agreement- HFF, Extension [Member] [Member] [Member]
Line of Credit Facility [Line Items]
Line of Credit, Current	$ 0	11
Line of Credit Facility, Maximum Borrowing Capacity	$ 0	175
Pricing on the Facility based on market rates	LIBOR plus 1.25%
PNC Agreement- HFF, Extension [Member] [Member]
Line of Credit Facility [Line Items]
Line of Credit, Current	$ 239.2	151.6
Line of Credit Facility, Maximum Borrowing Capacity	$ 500	1,000
Pricing on the Facility based on market rates	LIBOR plus 1.25%
Agreement expires September 19, 2020, Extension [Member] [Member]
Line of Credit Facility [Line Items]
Line of Credit, Current	$ 1,016	184.8
Line of Credit Facility, Maximum Borrowing Capacity	$ 1,200	775
Pricing on the Facility based on market rates	LIBOR plus 1.40%
Agreement expires August 31, 2020, Extension [Member] [Member]
Line of Credit Facility [Line Items]
Line of Credit, Current	$ 85.1	11.4
Line of Credit Facility, Maximum Borrowing Capacity	$ 200	100
Pricing on the Facility based on market rates	LIBOR plus 1.40%
Fannie Mae ASAP program [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Repurchase Amount	$ 84.3	53.6
Debt Instrument, Interest Rate Terms	LIBOR plus 1.15%
Line of Credit, Gross [Member]
Line of Credit Facility [Line Items]
Line of Credit, Current	$ 1,724.8	516.8
Line of Credit Facility, Maximum Borrowing Capacity	$ 2,275	$ 2,425

Commitments and Contingencies_2

Commitments and Contingencies (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
Loss Contingency, Receivable	$ 41		$ 37.7
Loan subject to loss-sharing arrangements, aggregate unpaid principal amount	11,000		9,700
Loan loss accrual	20.7		$ 20.6
Insurance Claims [Member]
Loss Contingency Accrual [Roll Forward]
Loss Contingency Accrual	38.1	$ 43.1
Loss Contingency Accrual, Provision	5.8	0.1
Loss Contingency Accrual, Provision Adjustment	0.8	(4.4)
Loss Contingency Accrual, Payments	0	(1.1)
Loss Contingency Accrual	$ 44.7	$ 37.7

Restructuring and Acquisition_3

Restructuring and Acquisition Charges (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Restructuring and Related Activities [Abstract]
Restructuring and acquisition charges	$ (33.5)	$ (70)	$ (75.8)	$ (114.3)
Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability	(0.6)	0.7	(8.2)	20.7
Share-based Payment Arrangement, Noncash Expense	6.2	14	30.5	14
Restructuring reserve [Roll Forward]
Restructuring reserve, beginning balance			36.5	15.1
Restructuring charges			53.5	79.6
Payments made			(58.5)	(77.5)
Restructuring reserve, ending balance	31.5	17.2	$ 31.5	17.2
Document Period End Date			Sep. 30, 2020
Severance [Member]
Restructuring reserve [Roll Forward]
Restructuring reserve, beginning balance			$ 24.3	14
Restructuring charges	19.3	7.2	27.6	17.6
Payments made			(22.1)	(21.2)
Restructuring reserve, ending balance	29.8	10.4	29.8	10.4
Contract Termination [Member]
Restructuring reserve [Roll Forward]
Restructuring reserve, beginning balance			8.4	0.6
Restructuring charges			9.3	5.8
Payments made			(16)	(1.5)
Restructuring reserve, ending balance	1.7	4.9	1.7	4.9
Lease Exit [Member]
Restructuring reserve [Roll Forward]
Restructuring charges	8.6	48.1	25.9	62
Other Restructuring [Member]
Restructuring reserve [Roll Forward]
Restructuring reserve, beginning balance			3.8	0.5
Restructuring charges			16.6	56.2
Payments made			(20.4)	(54.8)
Restructuring reserve, ending balance	0	1.9	0	1.9
HFF Acquisition [Member]
Restructuring Cost and Reserve [Line Items]
Business Combination, Integration Related Costs	$ 13.8	$ 60.1	55.2	$ 69.8
Restructuring reserve [Roll Forward]
Expense to be recognized for retention awards			$ 100

Accumulated Other Comprehensi_3

Accumulated Other Comprehensive Income (Loss) by Component (Details) - USD ($) $ in Millions	3 Months Ended						9 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019	Dec. 31, 2018
Accumulated Other Comprehensive Income (Loss) [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ 5,286.2	$ 5,109.4	$ 5,028.9	$ 4,858.1	$ 3,875.3	$ 3,795.1	$ 5,286.2	$ 4,858.1	$ 5,204.7	$ 3,734.5
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax and Reclassification Adjustment, Attributable to Parent	0.7			0.1			0.7	(1.7)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax, Portion Attributable to Parent	59.3	33.8	(143.4)	(34.6)	(23.3)	31.3	(50.3)	(26.6)
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	(71.3)	(72)		(59.1)	(59.2)		(71.3)	(59.1)	(72)	(57.4)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	0			0			0	0
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	0.7						0.7	(1.7)
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax and Reclassification Adjustment, Attributable to Parent	(0.7)			(0.1)			(0.7)	1.7
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	(406.1)	(465.4)		(425.4)	(390.8)		(406.1)	(425.4)	(355.8)	(398.8)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	59.3			(34.6)			(50.3)	(26.6)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	0			0			0	0
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax, Portion Attributable to Parent	59.3			(34.6)			(50.3)	(26.6)
AOCI Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	(477.4)	$ (537.4)	$ (571.2)	(484.5)	$ (450)	(425.9)	(477.4)	(484.5)	$ (427.8)	$ (456.2)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	59.3			(34.6)			(50.3)	(26.6)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	0.7			(0.1)			(0.7)	(1.7)
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax and Reclassification Adjustment, Attributable to Parent	0.7			0.1		$ (1)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	$ 60			$ (34.5)			$ (49.6)	$ (28.3)

Subsequent Events Subsequent Ev

Subsequent Events Subsequent Event (Details) - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Subsequent Event [Line Items]
Common Stock, Dividends, Per Share, Declared	$ 0	$ 0	$ 0	$ 0.43